As do any of the 100's of ground blinds being sold and (to a lesser but still a significant extent) tree stands - depending on heigth.

You can pull an 80%, 50# compound (10# hold) rest the lower limb on your leg, and hold easily several minutes and still make a killing shot.
And there are some models now adjustible up to 99% letoff. These methods and equipment seem to meet the "removes the challanges" arguement every bit as much as the xbow supposedly does.

Something to think about is all.

Steve