Here's how I play the KIA.
1. Set up that thematic e5 push.
2. Make the e5 push.
3. Watch my position go kaboom.
Ignore, for a moment, the material drops at the end -- I think it's clear that I was lost by move 23, and before that there weren't any tactical problems that I can see (the actual e5 push was a little hairy, but on the lines I've looked at so far where the knight takes, I end up either keeping the pawn or with well-placed heavy pieces).
On the other hand, when I don't take the push... even in the face of overwhelming temptation, I do fine! e.g.:
edit: GAH, what does the page want from the pgn files?!