Here's Mark Rippetoe on CrossFit from a TNation article:
Testosterone: Coach, I know you've been certified through the NSCA since 1985 (with their first certification group), you've been a competitive powerlifter, and you've been involved with Crossfit. How'd it all come about?
Mark Rippetoe: I don't read around the web much, because I'm old and busy, and just haven't got time. If I'm on the Internet, I'd rather be looking at porn. So, I didn't really see anything about Crossfit for a long time.
But it came to my attention a couple of years ago, and I just recognized it. I may have minor methodological problems with them, but they're the only organization I see with momentum that's moving in the right direction.
They advocate basic methods of human movement that all serious trainers have used for a long time, and they've formalized the process through randomness. Crossfit doesn't pretend that they're anything but GPP [general physical preparation]. We're not saying powerlifters need to do Crossfit. We're not saying Olympic weightlifters need to do Crossfit, or bodybuilders.
But for people for whom the random use of their body, and physical abilities, comes up at work or for certain sports, Crossfit is the best program out there... for them. We're not saying that it's anything else. But it is, quite literally, the best synthesis of all this stuff that's been formalized.
If you look at Crossfit from the standpoint of, 'This is what they're trying to accomplish for these particular athletes,' I don't see that there should be any controversy about it at all.
T-Nation: Sometimes there does seem to be a misinterpretation of those goals. While it's not ideal for bodybuilding, it does appeal to a lot of firefighters, law enforcement, and the military. I think people in those lines of work seem drawn to it.
Rippetoe: I do too, because it works. One of the reasons our methods fit into Crossfit so well, is because the stronger you are, the more effective you are at Crossfit. Lots and lots of people have figured that out through experience. And that's why we're so widely accepted as a nice adjunct program, at least in terms of our methods detailed in Basic Barbell Training.