I think Davone Bess might have been a product of Chad Pennington. Bess has not been the same since Penny got hurt. He doesn't get near the same number of catches, but also doesn't get nearly the same number of targets either.
Bess has a quick first move, but is pretty slow as WRs go. Penny anticipates where a WR will be coming out of a break, and throws early and accurately. So when Bess makes a quick move and gets open for a second, penny's ball was already there.
Henne does not have this same anticipation, which probably comes with lots of experience. So Bess is always covered again, by the time Henne sees him come open for a quick second. if that makes sense...
ALso Henne's passes are generally thrown alot harder than Penny's, maybe Bess doesn't have the good hands to catch a ball with some velocity on it?
Just a theory...