I think that the term 'consequence' was chosen very deliberately, and the choice to take a consequence should require some thought. By allowing consequences to be 'healed' readily, my guess is that those consequence boxes will be treated as nothing more than additional stress boxes, to be checked off then healed by the party healer after the fight. That said, I think that a limited form of consequence reduction is not unreasonable, and the ability to change the nature of a consequence might work, too. Here's my thought on how magical healing could be used:
1) Magical treatment of injuries. This just starts the character onto the natural healing process, but doesn't speed things up. Mechanically, this is just a "Thaumaturgy Simple Action" (YS264) applied to the rules for the mundane medical version of treating consequences (YS220). The complexity would therefore be 2, 4, or 6 for mild, moderate, or severe. This application would only actually be of use to characters that do not have Wizards Constitution or one of the Recovery powers, as they don't need anything to jump-start the healing process.
2) Consequence reduction. This speeds the healing process; any 'healed' consequence is treated as being one level less severe for purposes of healing time (though it still occupies the original consequence 'slot' until the consequence goes away). Mild consequences would disappear right away. Mechanically, use the Reiki Healing spell rules (YS300). The comments for using the spell on higher wounds was not entirely clear to me, but I think the intention was basically to add the numbers above to a base complexity of 4. So 6, 8, or 10 for mild, moderate, or severe. I'd be tempted to say that these numbers are low, I'd probably make the difficulties cumulative, which would be 6, 10, 16, instead. (I.e., serious would be 4 (base) + 2 (mild) + 4 (moderate) + 6 (severe) = 16)
3) Consequence modification. As one final option, it might be reasonable to allow magic to change the nature of a consequence, thereby re-wording the consequence. The consequence takes the same amount of time to recover from. An example might be to 'heal' someone with a Broken Leg (severe consequence), rewording it to Limping Badly (still severe). Now the character can walk on his leg without crutches, but still has trouble. Mechanically, nothing's changed, but in DFRPG the 'flavor text' can be important. I think the complexities would be similar to #2, noting that the magic would be in addition to #2 and would work on the original severity of the consequence. If you want to do both, then double the consequence level before adding to the base.
As a note, this seems most applicable to physical consequences. I could see it being used for mental consequences ... but keep in mind that this is
*exactly* what got Molly in trouble
.