The loop is definately a factor.You can look at my draw length in my first video and see that I am too short but that is the draw length I am shooting but just with a longer loop.
This is why I alway tie on a "Catfish Loop". It wil not stretch, even a little and therefore allows my hand to be closer to the string than tying one with regular loop cord from a bow shop. In addition there are lots of other advantages to a Catfish Loop. The only disadvantage - you have to spend 10-15 minutes tying one.
Learn how to tie one here:
http://www.racksandspurs.proboards38.com/index.cgi?board=techbow&action=display&thr ead=1143505027