Age

Why does Kobe seem old and Dirk seem in his prime, yet they are both the same age: 32? In fact, Dirk looks better than I've ever seen him play. More confident, better shooter. Kobe can once in awhile summon that extra gear (like in the Charlotte series for one game), but he simply cannot get around players like he used to and needs to settle for jump shots. Jordan was like this towards the end as well. It'll happen to all mortals. I suppose there are two easy explanations:

1. Quickness matters more to Kobe's game/position. If Dirk loses a step, it doesn't really matter. His speed was never the key to his game away. It is size and shooting ability.

2. Kobe has more wear and tear. Despite their ages, it does seem like Kobe has played a lot more games and a lot more big games.

Some other possibilities - Kobe cannot improve his shot. They way Kobe shoots - without much arc - is basically maxed out. Kobe has always been a streak shooter and more will than skill. His game was a combo of being able to get to the hoop and hit shots from anywhere. Now he can't get to the hoop, so strong defenders can play right up on him, making his shot even more difficult to get off. And he can't improve his shot because he already has maxed it out. In contrast, Dirk seems to have become a better shooter. He's always been good, but these playoffs, he seems to be nailing an incredibly high number of jump shots. And his game isn't based on getting around guys. He needs about 1 inch of space and he shoots from behind his head and who on earth can block a 7 footer shooting from over his head? It looks to me like Dirk could play for 5 more years and be effective. Even if he slowed down - he could play 3, 4, or 5 position on any team. Peja gets minutes. That guy can't even run and I'd take Dirk in a 3point contest over Peja (although I doubt stats would bear that out). He just bangs his shoulder into someone and pulls a fadeaway.

Another interesting player to throw into this mix is Ray Allen. He's old. He plays Kobe's position. He seems to defy age. This clearly has to do with shooting. Ray is the best 3 point shooter of all time. And he gets his shot off quick. His shot isn't dependent on getting to the hoop. He gets to the hoop sometimes because people fear his jump shot.