For me, it was 10. Nd1 that really changed this game.  I would not have played that.  I'm sure it's one of the reasons I'm not to good.  But basically, by moving the knight down, Wall makes room for the queen attacking the black kingside.

 

If you look at the board from this point in the game, it's like Bill has opened a door way with the A, B, and C pawns for the queen and bishop double-diagonal pressure.

 

It's this point where Black is boxed in.  His knights are blocking the attacking power of his bishops.  This is a position I often find myself in.  I've developed but sometimes against better players, nothing useful comes of it.

bill, you make it look too easy :(