AF modes when shooting fast moving objects. As some of you know, I shoot dog agility events here in the N.E. Lately, I have been struggling on and off with the D3 and its ability to focus on the dogs. The issue is most apparent when trying to photograph a dark dog. The AF simply stops. To say that the end result is a soft picture is an understatement. I have tried single point, dynamic area (9,21, and 51pt) with no change. I have also tried the various setting of the "focus lock" set on short, normal , and long. I have also tried "off". Of course I am using CF AF mode. It really became apparent when I was using the D3 along with my D2x this past weekend. The D3 shots looked "soft" and the D2x shots were spot on sharp. I was a bit upset to say the least. The D3 has the latest firmware and I don't remember this issue when I first bought the camera. Anyway....I guess what I am asking is what AF lock setting do you find produces the best results? Do I just keep it off, so that the camera refocuses instantly, or do I use the delay? FWIW, the camera was sent to Nikon today for a LCD issue, but I asked them to please go over the AF system extensively.