I meant your countered stance/tendency to not keep your body in line with the board. Snowolf described it much better in his post, so just refer to that.
My, you have big feet
Size 9 on the 152 Proto should be fine. Judging from the videos, you certainly do not have too much overhang.
Maybe stand on the board with bare feet and see whether your toes and heels reach the edge of the board - or measure following Wired's excellent explanation here
I suspect that that might be the case. Is he riding a wide board?