Rocky just waking up. He hates getting his picture taken.
CrossFit's programming was developed by empiricism holding precedence over therory. This concept is known in the CrossFit community simply as "The Black Box". We put stuff in the Black Box(inputs) and observe what happens to those inputs when they come out(outputs). If the change is positive we use it. If there is no change or the change is negative we toss it. Here's an example: If I give Bob 6 weeks of programming and nutritional planning and he comes out of that 6 weeks with a 7sec faster 400m, a 10# increase on his snatch, 10 more pull-ups to his max, and 2% less body fat I know it worked and really don't care why. We only care that it's measurable, observable, and repeatable. We measured Bob's success with true numbers, we saw Bob's success, and now let's put a bunch of other folks through the same program to duplicate Bob's success.
There are a ton of ways to do pretty much anything. Eat, exercise, communicate, live, etc... Don't let someone else's "principles" or "therories" get in the way of what works. I know, real obvious right. You'd be suprised how many times I hear a confident voice proclaim "But you can't work legs after you just worked legs yesterday" or " You are burning too much muscle because your heart-rate is higher than the fat burning zone". The same voice has a 135# max squat, can't run a mile in less than 10 minutes, and is over 20% body-fat all with following their workout "principles" religiously for over 5 years.
What I love about CorssFit is that if something emerges that is more effective than the current programming for the goal of "being fit" CrossFit will use it, as long as it's measurable, observable, and repeatable.