OOP: Inadvertant/Incantationless Magic

[J]

No: HPFGUIDX 63902

Did anyone catch the part when the Advance Guard enters the house 
and Harry, who is supposed to be LOCKED in his room hears them jumps 
up, grabs his wand, and listens with all his might and the door 
suddenly unlocks and opens? There was no one else outside the 
door to open it. Did Harry inadvertantly do this? 

A counter argument could be that Moody can see everything in the 
house and may have unlocked it from downstairs, but I think that 
would have been mentioned or he would have asked why Harry was 
locked in the room.

This also builds upon the wandless, incantionless "magicking" open 
of the cupboard under the stair that Harry performs just after 
blowing up Aunt Marge in order for him to get his trunk and things to 
leave in PoA. 

JKR has said wandless magic is imprecise and unfocused but this 
magic seems pretty precise. Granted, this time in OotP, he DID have 
his wand and was indeed focusing intently on hearing so maybe the 
wand in his hand channeled his mental focus to perform the magic. 

Also, in the first chapter when Harry jumps up from under the window 
outside the house, Uncle Vernon grabbed him but had to let go of 
Harry because he was "as if shocked" by some jolt. I wonder if this 
jolt has any relation to the 'stinging hex' that Snapementioned he 
felt when Harry first shirked off the Legilimens in the 'Occlumency' 
chapter. We never hear a specific hex shouted, Harry just says 
something like, "No! It is too private!" and then thows off Sanpe's 
Legilimens.

During Dumbledore's and Voldemort's fight, we seem to see a lot of 
magic where they each conjure things but never hear the incantations, 
whether that is because Harry never hears them or because they simply 
are not important (not likely), I think maybe it seems like both DD 
and V can do incantationless magic--magic focused by intent alone. 
Another example of this may also be Dolohov's curse of purple flame 
that got Hermione that was said while he was under a silencing charm. 

Arya