Wand Switching (Was Peter vs. Sirius once again)

[Kirstini]

No: HPFGUIDX 59505

gamer5255 wrote:  Picture it: the last ANYONE saw of Peter 
 before this incident was right before he transformed. Why is 
everyone convinced he left directly afterwards? My theory is, he 
SWITCHED BLACK'S WAND WITH HIS OWN. It's plausible that part of 
Sirius's 'shock' reaction is dropping his wand, right? And he might 
not notice a rat at his feet in that same shock. So, Pettigrew, as 
a rat, switches the wands(carrying them in his teeth) so the wand 
that performed the 'explosion' spell is at Sirius's feet, and 
the 'innocent' wand is near Peter's robes. 

Kirstini (popping her head up from the life du lurk):
Hello! The trouble with this theory is that we know that wands, 
being personalised to the wizard/witch, don't work as well when used 
by someone else. Peter is not a very good wizard - we have numerous 
canon references to back this up - so therefore would be even more 
limited in the "Flesh of the Servant" spell without his own wand.
I have a funny feeling that all this constant reference to 
Pettigrew's ineptitude is significant. He appears to have managed 
most spells pretty well so far... 
 I don't think anyone even bothered to PI Sirius's wand, as there 
was enough "evidence" to convict him anyway: presumed Secret Keeper, 
dead Muggles, Pettigrew's finger.
anyway, back to lurk, 
Kirstini