I've been thinking about a "Thief with the Magic touch" (a focused practitioner, who uses magic to help his thievery).  Suppose he's got Burglary +4, Conviction +2, Discipline +3, Lore +1.  I'm trying to understand how to pick a +8 lock using a spell (i.e. by creating a Burglary +8 simple action).  [Any easier a lock, and he could just use Burglary, aided with a maneuver and a little luck.]  Of course, for dramatic purposes, I'm assuming the cops will be coming around the corner any minute!

I'm imagining that he is going to envision the careful motion of the pins in the lock (maybe aided by the Sight), then push them "just so".

At first I thought I could do it with an Evocation, since I was thinking it could be quick and on-the-fly.  But Evocations are really about combat, so now I figure it's Thaumaturgy.  But although the casting of the spell is reasonably simple (say, a few exchanges, just like on YS271), the preparation seems impossible.

I'm thinking that the spellcaster does not need a symbolic link, since the lock is right in front of him.  Perhaps his Burglary skill lets him make a declaration to get +2. Maybe a bonus or two due to a focus and stunts.  But I don't see how he can get the 7 shifts of preparation he needs to do it on-the-fly.

Am I on the wrong track here?  Or am I exactly right, and casting a Burglary +8 spell on-the-fly would require some major spellcasting ability,  more than, say, a -6 refresh could allow?  Maybe someone more junior has to find another way --  by prepping in advance, with a bit of "casing the joint" to get info (and a symbolic link)?  Or maybe he needs a set of Enchanted Lockpicks?

I'd appreciate any thoughts.  I'm impressed by the system, but a little surprised that I'm having so much trouble massaging it into the shape I'm aiming for.