In the 11' I can find much less calf pressure but I half to be careful, because if I don't watch for it a leg will fall asleep. I never had that problem with my HH. When I find the sweet spot/angle in the 11', there's almost no calf pressure at all. I was never really able to get rid of all the calf pressure in the HH, unless I was in a tight fetal position because I was cold.
I think that some calf pressure is probably just part of the gathered end hammock. It how you work with it that makes the difference.