That's not the player trying for an outcome, that's the character.  Except that the character doesn't know what Aspects or Fate Points, or 'Tags' are in the first place, and so doesn't need to know how many would need to be involved in order for them to succeed at their task.

In doing so, you deny the players the ability to play their characters effectively, evocatively, and often, satisfyingly.
Without such information, they cannot make the necessary decisions as to whether or not they should spend resources that do not exist in the game-world, but nevertheless affect it.
The character is doing research.  The player is spending FPs (or not, depending on whether or not the they deem it worth their while).

I disagree. All your doing by telling them explicitly what you're going to give them for certain rolls is turning FATE into a video game. This isn't fallout, where you see three options and if you have a high enough bluff skill you can chose that one, otherwise you chose one of the other two options. In the spirit of Dresden especially, my view of it is the players have to do the best they can with the information they've got, and hope they aren't too far off the mark.

Again, I'm not advocating not telling your players the targets - quite the opposite. By and large you should be telling them - especially if they ask. But if they don't even know IF there is a target? I'm not going to tell them, no.

An example. My players characters walk into a building that they are not sure the fleeing suspect went through - they immediately begin searching for clues that the bad dude came through here. He did by chance, but he covered his tracks well, using some magic talent that the group does not know he has yet. I'll ask for a roll - if the group asks, I'll give them an estimate difficulty - normally it might take a 3 in survival to spot something like that on the average mugger. They roll a 4 and move on, but a 5 or a 6 might have revealed signs of his passing and, possibly, that the tracks were covered magically.

Now why did I do that? Well, firstly, because as a story teller, I think it'd be more interesting if the players (not just their characters) didn't know that the bad guy went that way - but do want to give them a fighting chance of succeeding, even at this early juncture. I also would like them to think outside the box - catch the bad guy with cleverness and guile or else they will simply be outsmarted by the bad guys who make a point to rule out the more obvious ways of defeating them. The bad guy cant exactly out smart them if I just tell them that he's raised the difficulty, can he?

Now, this might not be everyones take on it - but I don't think it ruins anyone's fun to withhold meta game info just because of the fate point system. So I stand by my statement - if they don't know that there IS a target to hit, there's no reason to tell them.

Without having at least a decent idea of how well your character succeeded (or how badly they failed) it becomes difficult, at times impossible, to make the necessary metagame decisions upon which this system is based, such as whether or not to invoke an Aspect to boost your roll.

Ah, now you're getting into a whole different can of worms - should you tell your players how well they need to roll for a success! This is something that the designers of the FATE system have implied strongly, but never actually given a definitive answer.

My answer to this is usually yes - within reason. If a player is trying for an outcome they explicitly know - such as lifting an object, shooting a target, or overcoming an enemies armor - I will gladly tell them. Heck, I'll volunteer the info. If a target is a little hazier - those rolls where the player is fishing for info from the GM (like looking up info at the library, or searching the scene of a crime) then the goals are a little more vague. Again, this is a discretion call - if they want a particular fact from a research roll - say a famous figures birth date, I may give a set target, but not if they cant tell me exactly what they want to know. I'm not going to tell them that there is a reward for hitting a 3, two rewards for hitting a 7, and a ton of stuff for hitting a 10 - they might have a vague idea how thorough they were (e.g. they know what the dice roll was) but that's it.

Many people want to hear that the answer to this is clearly yes, but in the fate system, just like in real life, the answer is not always as clear cut as yes or no.

There are different types of reaper / shinigami - you might want to explain the lore a bit more. In this setting, what is a true Shinigamis job? What would you like to do power wise?

I guess that puts me back at where I started - that declared visions, while not specifically against the rules - would probably by and large be vetoed unless they were extremely clever ways of making the story more interesting then I originally planned.

Actually, on another note: it occurs to me that if you don't like the meta of pretending to not believe a prophecy then there's another way you could play the downside - perhaps sometimes the prophecies are randomly symbolic? For instance, if you see a city in flames, that could mean that the city is going to literally burn, or it could mean that the important relic is at a shop in the city called 'in flames' - or that the hot chick you met at the bar last week is in the city. I'd need to think up some ways to keep it so the vision is still somehow useful - but it's a zero refresh power - it's not like the visions always HAVE to be useful after all.

The reason Cassandra's Tears doesn't have a cost is because it has a built-in penalty. Never forget that. The player should always have an uphill battle convincing anyone of the character's visions. If the character declares a vision through Cassandra's Tears, that means everyone else should actively disbelieve them. I know, it might be hard with the metagame, but without that penalty the power isn't being used right.

So even if a character declares through a vision something that will work in their favor, they'll still have to work to take advantage of it because nobody will believe them and help them take advantage of it.

I'm ok with declarations in a vision to some extent - but players initiating a vision seems like it's pushing it - even with the -2 to get people to believe it. Could be gamed way too easily. For instance:

Good - The GM says 'you have a vision! Billy the NPC will try to backstab you!"
Player - *making a declaration* 'But not until after we get the kid to safety!'

Bad - The NPC requests the players retrieve a mystical chalice.
Player - *making a declaration* 'I've had a vision! The chalice will be in a garage sale by some old lady in Utah for cheap!'

I think this is more me wanting Cassandra's tears to not be the only plot device. It's almost artistic taste at this point: I want to use something to compliment the broad strokes of that particular brush. Unfortunately, the PCs are a little on the 2D side so far - partially because the players are still used to D20 style gameplay, and partially perhaps because we haven't had too much time to flesh out personalities yet.

In this case, I'd like to play on the nature of her visions and make the vision a direct result of his actions, but I see what you mean. This should be about a massive compel of her concept, rather than an attack on her stress track. Perhaps I'm thinking too much like a character when I'm supposed to be the GM. I still like basing my actions as being a result of an NPCs actions though...

OK, so I've been mulling this over for a bit. There is an old standby that says that if failing a roll wouldn't result in anything, don't call for a roll. I generally interpret it as thus:

1) If the roll has no real relevance to the campaign, don't call for a roll
2) If the PC can't possibly fail or succeed, don't call for a roll
3) (Recently learned) If the player has recently made the roll doing something similar, don't call for a roll. Use the recent result instead.

Now, that said, I wanted advice on how to handle a scene. I was planning on having an NPC introduce himself by essentially showing the groups seer a vision of hope - considering her visions are by nature always graphic, horrible and depressing, this should come as quite a shock. I was considering this as a mental attack that would place an aspect on her for the duration of the story and hopefully suggest a new permanent aspect in the future. I'm considering this as an autotakeout - so I'm thinking I have three options:

A) Big mental attack, enough to one shot her mental stress attack. Give her the option of trying to fight it off, but compel her not to.
B) Massive mental attack. Don't bother letting her roll as per the rules above.
C) Find another mechanical way of modeling this?

I should mention, this is a plot device, not really screwing the players over so much as making sure they pay attention to the badass NPC. If I go with A, the Aspect should probably screw her over a little, so I'm leaning towards that, even if I have to compel her with 2-3 Fate points.

My question is, am I trying to railroad the players doing this? I'm new to this and trying to determine how best to accomplish this. The best I can do at the moment seems to be railroading them into wanting something (since as PCs, the players haven't really given their characters much by way of wants, needs or passions.) My best guess on how to handle this situation is to railroad them into a goal, then let them figure out how best to accomplish that goal (while planning out the obstacles to the most obvious routes to that goal and preparing to improvise when they take a less obvious route.)

So, I'm trying to build a location with a lot of aspects - I'm trying to teach several players the game and would like a fight scene where I hand them their asses unless they can figure out the fighting para-dime - aka stop directly attacking and work as a team, setting up lots of big attacks instead of kamikaze attack strategies. I notice however that there aren't any resources for this, so I figured nows a good time to start a thread, getting people suggesting different scene aspects.

The nice thing about scene aspects is they're easier to write then character aspects - there's no set number required in a scene, but the more you have the better.

Off the top of my head:

Rickety 300lb chandelier
Gas main
Dark and shady forest
Obscuring brush
Camping garbage
Piles of kegs!
Firepit
Hard Ground
Soft Ground
Unstable ground
Fresh dew
Angry birds
Hidden hatch
Shoddy electric
Boarded up windows
Cluttered floor
Piles of boxes
Dusty

Please suggest more! I don't normally list the required assessment because more of them I would allow for almost any type of roll, but create different difficulties depending on how related they were. For instance, if a player really wanted to do an assessment using their 'driving' skill, I'd allow them to discover 'weakened wall' at a fairly high roll - after all, they'd know they could probably be able to drive through that wall fairly easily if push came to shove, which might mean they could use that knowledge to their advantage.