This is a tough issue that I battle when going into the gym and a very valid argument against Crossfit. Let's look at it from both sides.
First why it's bad. Obviously it is the fast track to injury. When in a fatigue state and under time duress, form goes out the window and one resorts to any means to move a weight. Doing highly technical moves in such a state also reinforces bad motor patters (bad habits) that will remain in non fatigued form. Finally you are bastardizing a movement that takes a lifetime to perfect.
Now the benefits not necessarily why it's acceptable. Although the fast track to injury, it is also the fast track to gains. You will not stress both neuromuscular and skeletal muscular systems as effectively into adaptation under any other form of training. More pain resulting in more more gain. It also takes 10,000 reps to master movement pattern. High reps will get you there faster if proper form is maintained.
The problem 99% of the time is that coaches and athletes do not know where the line between gains and injury are. You are straight up playing with fire. You will get burned. I am one of those guys.
IMHO only trained firemen should be allowed to play with fire. Unless an athlete can demonstrate correct form and has enough experience with their limits should they be allowed to go balls out on an oly move.
Proper coaching is mandatory. The coach has to be able to visually recognize when an athlete has crossed the line into the danger zone and push the eject button. The coach also has to have knowledge of an athlete within a few reps to know how to scale a movement for an athlete.
For example, I would not let a beginner do a clean or snatch amrap from the ground. Until they can display proficiency of the second pull from the hang, why add more complexity into their skill development? I wouldn't even let them catch in a squat and keep the weight light enough for a power variation. So strictly 2nd pull work. And if they are really awkward with the barbell they are doing kettlebell swings instead.
Finally there must be humility on both coach and athlete. Check the ego at the door. Better to fight another day than lay it all on the line for a workout. Now at a regional or games competition is another story. You are doing it for glory, country and pussy at that point. Might as well lay it all on the line.
There is a smart way to do Crossfit. But unfortunately any idiot with $1000, a weekend, and half a brain can get a tshirt and piece of paper that says they can open a gym to coach people to do high rep Olympic movements.
I was one of those guys. Then I had an epiphany to learn as much about training as I could just so I wouldn't hurt myself but more so to be able to walk on the razors edge between injury and super compensation. And thus maximizing my human genetic potential.
Short answer: find good coaching, know what you are getting into and buy into it.
Lots of knowledge in here. So just being devil's advocate, can someone explain to me the reasoning behind taking highly technical and complex oly lifts and doing AMRAP in a short period of time? Seems like the perfect way to throw form and safety out the window and get injured. I personally know half a dozen former "crossfitters" who have been injured using this genius approach. I'm a bit biased, but I would like an answer, no one seems to be able to give me a decent articulated rationale behind, for example, doing power cleans as fast as possible.
