Sorry to be confrontational, but there are few aspects of motorsport that require a faster lens than a normal screwdriver AF lens on a fast body. Unless one is talking about the 200/f4 Micro, they're all fast enough - "useless" is absolutely not a word I agree with. I have done the experiment, and it is straightforward to shoot motorsport with lenses such as the 70-300/f4-5.6 AF D ED - on a D100. I've even done it with the Tamron 90/f2.8 AFD Macro and the 200/f4 AFD Micro-Nikkor.
As I said, I don't shoot hockey, but I do know motorsport reasonably well. With the possible exception of one specific type of shot, I am 100% confident that a D3 with a 300/f2.8 AF D will get all of the motorsports shots. The single exception is on a full speed straight with the car coming almost directly at the camera - that one is pretty tough, although frankly I think it will get that one too. It's more a matter of the AF system than the lens, since the D2x does NOT get that shot even with the 400/f2.8 AFS, which is the fastest focusing lens I know of. See this thread for pictorial evidence.
Again, I don't know that hockey is the same as motorsport. But the assertion that screwdriver AF is too slow for motorsport is not correct.
_____ Brian... a bicoastal Nikonian and Team Member
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