I disagree though. As athletic as he is you'd expect him to be somewhat of a lockdown defender on the perimeter, but he gets exposed from possession to possession. To be honest it seems like he's more content hanging around the paint and pretending to be able to block shots than actually getting down and playing solid on-ball defense.
His rebounding is overrated - I've never seen the guy actually get down and dirty and block out, the only rebounds he gets are the ones that fall into his hands or can be jumped for.
As far as deflections go, I actually find Kapono does a better job of covering the passing lanes than does Jamario.
Having said all that it's not that I think Jamario is uncapable, I just think he's comfortable, and doesn't apply himself.