Lol I just browsed trough all your Nascar shots on Flickr, I love your photoset! It's like watching photos from tourists who don't want to take the standard shots while visiting a big town. I love it! I expected lots of racing cars and panned shots, but this is way better. I wouldn't want to sit by the fence for three hours raking the same photos on different cars. A few of those are great, but this is way more interesting.
It must have been quite a big event as well with so much photographers and an F-15 fly-over. Too bad you didn't capture the cars jumping the banana.

As for Mr Bolt. I think if you had to take over his job without knowing how to do it perfectly, you would probably screw such an easy thing up I reckon. It's amazing how fast these guys are, but it's probably only possible by their good preparations. I really like the photo