I don't know if I understand exactly what you're talking about either, but I experience something that may be similar. When I apply too much tension to the string as I'm setting up, I tend to clinch the muscles in my hand, and they stay clinched throughout the shot, resulting in a poor shot. If I just place the string in my grip without putting much tension on it, it is easier for me to keep the muscles in my hand other than my hook relaxed throughout the draw, which results in a better shot. The string is in the same position in the first joint of my fingers either way, and my hook is equally deep either way, but there's something about having a very light pressure of the string on my fingers that helps me to relax my hand as I begin my draw.
I don't think it is necessary to begin your draw this way, but if it helps to keep your hand relaxed, I don't see anything wrong with it.