BuckAlley

Stability in some of the latest shorter ata' s isn' t just because of the length. Forgiveness comes alot with brace height, and the longer braces are found on alot of the shorter ata bows. Also grip has a large play in it. If your bow has a grip that feels very comfortable to you, and fits you well there' s less chance of bad form at the shot. Grips are very important, and often overlooked. Now if you took that same grip, and brace on a longer ata bow no telling what one could do that shoot the shorter ata' s.
Now on the other side of shooting well that varies alot too. Some can nail tacks at 20yds consistantly with a short ata. But try stepping back to 40-50-60yds, and see if your still capable of driving tacks! Thats where every little aspect of your bows specs, and your capabilities really showup. Thats also why you' ll see mostly longer ata bows in the 3D competitions.
Its really a simple concept of balance with longer ata' s. Picture walking the tight rope if you will. The longer the stick you hold in your hand the better your balance while walking the rope. Use a short stick, and balance is less.