I don't aim with the anticipation of the deer jumping the string but where I aim I feel I'm covered. I place my pin about 1/3 of the way up the deer. If it jumps the string I'm confident the arrow will take both lungs, if not I'm aiming for both lungs and heart.

I'm shocked that a relexed deer could jusp the string that bad at 15 yards. However you didn't mention wether or not the deer was relaxed.