IA investigator short and broad. Why does IA have the case? Divine intervention.

Only things missing for plausibility are:

1) Knowing how to use a sword- and all that takes is Murphy mentioning training with him
2) Mention of pronounced religiosity.

Post Peace Talk/Battleground WAGs

1)   Eb lays down his life for Thomas, not Harry, as a sideways apology
2)   Thomas is cured of his phage by the island- it was referring to the phage, and not Thomas, when commenting he barely deserved minimum security
3)   Harry binds the Titan. This puts a target on his back, because it was not known he was Warden. Control the Warden, control the island. He’s only using cheat codes when he’s there.
4)   The Round Table was created for one of two purposes:
a.   As an “endless supply” of well-trained KotC
b.   To provide Merlin with blood samples to use at Demonreach
5)   Harry finds out he’s the 4th KotC, and this is why Mab can’t stop Uriel from using Harry- pre-existing obligation.
6)   Not mine, but I’m onboard- Thomas becomes a KotC; he’s the son of a king.
7)   Harry’s only been saved by the WC because of his starborn status.
   The last time a starborn was running around, it was bad for Mab, the Winter Lady died, etc. I’m standing by my guess this was Kemmler, and he became a *Destroyer* instead of a *Starborn*.
9)   Longstanding, but restating: Starborn are walking conjunction points. Harry can kill an immortal whenever he decides to. He can also change the true nature of things. This in turn makes them immune to possession- within their own frame of reference, they are the fixed point. They’d have to *decide* to be possessed.
10)   Vadderung is/was Balor, not the Gatekeeper. Or he was Balor and gave his magic eye to become the Gatekeeper. Ethniu’s deference is filial.
11)   Ferrovax is the dragon that killed Beowulf, hence the antagonism.
12)   Elaine was the master in the Justin-Elaine relationship
13)   The Senior Council members spend a significant portion of their time in the NeverNever to extend their lifetimes; the war et al was partially to “age them out.”
14)   The Za Lord becomes a mantle- the Lord of the Dewdrop Fairies. Harry signs the Accords on *those* terms if kicked out of the Council. Mantle ability is a form of intellectus- Harry can know, if he thinks about it, what any of the faeries know, and speak multiple languages. He also gains a constant craving for sweets.
15)   Butter’s new sword can cut through “Titanic Bronze”; this is a significant reason why the KotC are involved.
16)   Murphy is dying at the end of Battleground, but becomes a Valkyire- and heads off to boot camp. Harry won’t see her for a century or more.
17)   The frying pan that dissolves was created by Maggie’s own conjuritis when she was thinking about pancakes.
18)   The references to Ivy and Hope’s physical maturity was to point out that Maggie was at an age to start the puberty they had nearly finished. In turn, this means her magic would start manifesting.
19)   The issue with Grendelkin is the size of the babies. Irwin exists because his mother is quite large.
20)   Thomas got Evanna pregnant and that’s tied into the “assassination attempt.”
21)   Harry’s treatment of the violin player/the ampule he put on Ramirez leads to Wardens changing their votes
22)   Little Chicago is used to coordinate defensive actions/communication
23)   The key to the story are the misdirections- Malcolm’s comment to Harry. What are the distractions?
a.   Thomas?
b.   The Peace Talks?
c.   The Last Titan herself?
24)   The Lance of Longinus is a perfect fit for the Blackstaff. Harry doesn’t want to think about that too much
25)   The Blackstaff cures Harry of his existing Black Magic taint. It’s “not worth it.”
26)   The real attack will be aimed at Demonreach again- conveniently near Chicago.
27)   When touching a coin, a Denarian can put a “shadow” of itself in you. If the Swords are also Angels, shouldn’t they be able to do the same? The Denarians can also teach you how to “summon” their coin. Is that how the Knights gain their knowledge of where they are supposed to be?
28)   There’s a lot of speculation that Lara’s haunted look at Eb reflected her doing him wrong. Possible, but it shows up after he comments that isolating you is what abusers do- and I’ve a longstanding WAG that it’s her own wedding ring that burned her; killed her own husband on her wedding night and he let her do it *because he loved her*, and that’s what makes Lara different. She has proof. The “haunted look” is memory, not guilt.
29)   Justine wants to go into witness protection to save her baby from the White Court. No-one considers this as the case- she called the FBI.
30)   The vampires are part of the accords because their dual nature protects them from Nemesis- it can infect the vampire, or it can infect the host, but it can’t infect both.

More as they come up. This was just from a first-pass read.

That is not only genius, I have an old friend who just got a sidegrade from schweinhund

My 2 cents, it was Kemmler.

   Great job, inconsistencies to bother me in a series.   The one that troubled me is the differences between Summer Knight flash backs and Ghost Story flashbacks as to what really happened when Harry came home early from school to be with Elaine and found what he found, and what happened.

I don't think this is an inconsistency. I think someone messed with Harry's memories

If time or reality are a toroid, inside Demonreach might be outside the Outer Gates.

That's if my WAG is correct, that the main purpose of Demonreach and the Warden is to contain the Nemesis-corrupted. So he's the counter-intelligence inside man, the cavalry for the Gatekeeper.

In which case, my other WAG- that it bleeds power deliberately from its prisoners, and that this is the true source of the ley line- might be it bleeding off the "cleaned" power.

Also, that the summoning circle exists for an ascension ritual for in extremis emergencies for the Warden.

Few comments:

If female WCV are fertile, then they're having periods. Males are still superior in terms of 24/7 fertility. I rather suspect Papa Raith keeps a few other males around specifically so they can breed 24/7 if necessary.

Also, I have long suspected, given that WCVs are never White Council level, that their Hunger fundamentally feeds on their magic. Corollary; all WCVs would be at least Paranet-level talents if not for their Hunger. Those like Thomas who have some serious magic anyway- opening portals to the Nevernever, tracking spells- are the ones who would have been White Council level.

Further potential corollary; the stronger your gift for magic would have been, the stronger your Hunger. Thomas's is particularly strong; which tracks having a mother who was a wizard.

I would posit that without latent "talent", they simply don't survive conception. So their birthrate is constrained by this. Since additionally most of them don't use magic, their own talents wouldn't influence their offspring a la Charity and Molly versus Molly's siblings.

This would explain the following:

1) Why the WCV haven't tried going after the Paranet talents before- their elders are aware this is cutting off their own population.
2) Why Lord Raith was interested in the not-quite-sex-goddess Margaret Le Fay- she's guaranteed offspring.

A few thoughts.
 
Chicago in general- it is a multi-layered crossroads. A freshwater port on an inland lake that connects to the ocean- twice. A major international airport hub. A railroad hub, a freeway hub. Located in the middle-ish of two mountain ranges, the Great Lakes, and the Great Plains, at the border of two nations. An old Celtic concept is that the more between something is, the greater the overlap with the Otherworld. Also, it’s a city in the sky- from a certain point of view. The entire city was lifted to solve a drainage problem in the 19th century; it’s on stilts. Canada is “cold”, the Great Plains are “hot”, and Chicago swings from one extreme to the other- it’s a good magical Law of Similarity for the “border” between Summer and Winter as well.
Venice would be your closest comparison, but is pretty definitely in Summer territory.
 
From a supernatural nations point of view; Europe is the primary stomping grounds of the White Council. South America was Red Court; one assumes China is Jade Court with a smattering of “they don’t do anything so White Council is there too.” Black Court was active in south-eastern Europe but was aggressively expansionistic; White Court appears to be Mediterranean originally (they speak Etruscan and favor the use of ghouls as muscle; ghouls speak Sumerian as a native tongue). Africa and Australia are unknown.
The White Council has been moving into North America, yet it seems that an effort to “recruit” in North America is new, like Ramirez-generation new. Let me suggest the following.
 
North America was *White Court* territory. This was a point of friction for New World wizards- McCoy, Liberty, Listens-to-Wind- and created a political block as a result in the White Council. Bianca was moving in to this territory specifically to assert a Red Court presence. Her success- right down to running a brothel, recalling that that would be what one would expect as a White Court thing- is why she’s promoted later.
 
The White Court previously published Stoker’s Dracula when the Black Court was threatening their territory in Europe (southeastern Europe).
 
Harry Dresden, walking magical boomstick, meanders into Chicago on his own, possibly originally for easy access to the Ways. He’s persona non grata in the Council and doesn’t interact with them.
 
Initially, he wanders into a turf Cold War between Bianca and Marcone. As a side effect, Bianca develops a personal hatred.
 
In Fool Moon, he embarrasses Madrigal Raith in front of the supernatural community (he was offering to auction Harry, recall).
 
Later, as a personal coup, Bianca attempts to kill him. Instead of directly violating the Accords, he releases his power to allow her dead victims to kill her and her  ... scourge? This is the pretext for the Red Court to declare war, but this does not void the standing of the White Council, making it an internal matter between the two. Winner: White Court. The incursion on their territory is neutered.
 
Paolo Ortega then challenges Harry to a duel. He loses.
 
Blood Rites- the White King is embarrassed by the White Council. His newest daughter is lost to the White Court and the Raith family. One assumes this is internally considered . . .an embarrassment. The Black Court has also established a presence in Chicago in this book; moving in to the “empty” territory?
 
Sidenote: Dead beat, Death Masks - the White Court is inert/embarassed, the Red Court lost their local powerbase in Chicago, the Black Court has abandoned moving in. Harry and the White Council aren’t flexing their muscle; making this an ideal magical Casablanca, explaining the Denarian and necromancer use of it. One assumes that the “dark ley lines” of Demonreach are part of their intended use of Chicago. Vastly powerful ley lines and no major supernatural nation providing oversight?
 
Main argument: Proven Guilty- this is targeted at Dresden, so it’s incidentally in Chicago. Dresden again embarrasses Madrigal Raith.
 
White Night- the White King is facing an internal coup. Malvora and Skavis are killing the next generation of the White Council before birth to show that “the wizards are vulnerable.” This is an insult that implies that the White King is seen as being in retreat/afraid of the White Council. This is “saved” for Lara by Harry showing up to eliminate the champions of Malvora and Skavis, making him appear as her cat’s paw when combined with their previous interactions. Instead, it appears Lara set up the other two Houses. The “power vacuum” in Chicago that Harry didn’t realize he’d created is filled by John Marcone. Lara Raith discovers that Harry is still protected by True Love from Susan, presumably when she attempted to use her power on him at the end of the book. He was an unanticipated threat at that point, being immune.
 
Small Favor- the Denarians make a play for Marcone or the Archive. And Anastasia Luccio seduces Dresden, out of the blue, removing his Lara Raith protection. Again, this can be seen as a territorial dispute revolving around Chicago.
 
Turn Coat- again, personal to Dresden. Chicago is incidental.
 
Changes, Ghost Story- Personal to Dresden. Red Court is eliminated. In the aftermath, we see Marcone and Lara fending off the Fomor.
 
Cold Days-  is really about Demonreach, which happens to be outside of Chicago.
 
Skin Game- Is personal. Mab has collaborated with Marcone for a vault with access to Hades’s vault to be located near the physical location of her Winter Knight.
 
 
Point is, what’s happening in Chicago is that Harry blundered into a turf war between two vampire courts; and his grandfather, being the Blackstaff, had enough White Council political clout to ensure that Harry was an actual full member of the White Council, with all rights and privileges applying thereof. Butcher tells us outright the White Court uses cat’s paws multiple times.
 
Returning to the OP:
 
1)      When one court moves, the other must respond. Both ladies being in proximity makes sense, regardless of Nemfection. I suspect it has to do with their purpose. At a *guess*, the Winter Lady’s job is to entice Changelings to Choose Fae, as part of a broader portfolio to supply soldiers for the Reality War. The Summer Lady may have the same job for summer Fae, or may exist to ensure that the Changelings have Choice. The Winter Lady’s seductress act would fit this portfolio nicely.
2)      The Summer Knight may have been in Chicago as a reaction to the budding turf war between Vampire Courts.
3)      Nice catch, I missed this. And Lea is one of the nastiest Winter Fae, yes? Kemmler was allied with “most of the wicked Faeries.” Probably includes the Erlking, too- goblins aren’t exactly nice. WAG: Harry is following a mirror Kemmler path, and this will be story important at some point. From the outside, he certainly looks a lot like Kemmler from the initial brief description we get. Speaking terms with nasties, keeps coming up with power-ups.
4)      I disagree here. I think it’s that the Knights aren’t bound by their power. A Fae not only lacks free will, but I imagine they can’t abrogate your free will either. Example: A musician told Maeve he’d give his life to play at a certain level. Maeve killed him by making him play himself to death, but *inspired* playing. If he hadn’t made that bargain, I don’t think she could have touched him. A Knight has the same freedom as any other mortal to frag anyone, even using their power. You irritate Mab but you don’t actually give her legal grounds to kill you? She can waste her time in elaborate vengeance, or just tell her Knight “That guy offends me. Deal with him.” No pretext, no cause- if Mab decided blondes were irritating, the Knight could go on a killing spree for her, as long as he could actually pull off the hit (Kincaid wouldn’t go down soft, nor would most of the Valkyries).
 
Additional note: One of my pet theories is that Harry isn’t the Winter Knight. Id-Harry is the Winter Knight, but Harry-Harry controls Id-Harry until he’s ready to make things go BOOM. This is part of what’s so attractive to Mab- a Knight who is master of the mantle, able to call on it, give it its head, or even tell it “stop that” depending on the situation. That would be why Id-Harry has the badge but Slate was branded.
 
I also have a super WAG that Harry’s not Harry, Id-Harry is Harry; Harry’s a fine thrall personality created so Id-Harry would be a controllable enforcer for DuMorne (immune/resistant to black magic backlash); but that Harry-Harry has existed long enough to “grow” his own soul, analogous to Lash-Lasciel. In fact, he would have been Harry-Harry for longer than he was Id-Harry.
 
Of course, my other WAG is that Harry is the 4th KOTC (Uriel’s Knight); and that’s why Mab is forced to accept Uriel’s intermittent interference. Since the other three are Faith (Gabriel), Hope (Michael), and Love (Raphael); my wife and I enjoy discussing what he might be the Knight of, my wife likes “Acts/Actions” and I favor “Judgment” or “Vengeance.” Puts a completely different spin on that scene with Cassius, when he claims to “repent” and Michael says, emphasis mine, “We can’t do anything to him”- and then the other three Knights process to let the 4th Knight break his kneecaps for information. HE can do something to Cassius. Faith in God, Hope in God, Love of God, Judgment of God.
 
The infusion with Soulfire would be analogous to Butter’s Lightsaber- it appeared when Harry went running into a Denarian ambush to save a little girl. His first use was a hand that literally smacked Thorned Namshiel around. Or maybe the Lance of Longinus is the 4th Nail. Or both.