Knight vs connected passed pawns

I found something interesting about the endgame 2 pawns vs Knight. I had played a game this weekend with this endgame (plus a few miscellaneous pieces on the edge of the board). That game drew so I put it into a endgame tablebase to see what the correct technique was. Interestingly enough, two connected passed pawns on the edge of the board cannot force a queen if the opponent has a Knight anywhere on the board except the corner. Check out the position.

White to move can force a win here. However, if you put the Knight anywhere else on the board White cannot force a win.

Neat. So what's the winning technique? Only one move wins. a6+

I just think it's cool that h1 is the only losing square for Black. In either position Black to move draws no matter what.