Really? It's his forward lean while catching the jerk that I've seen get criticized.
I've heard all things like this, but the ones who criticize have the proper proportions for the sport and have a hard time seeing the difficulty in attaining certain positions of the lift. They think it can still be done by those with unfavorable anthromorphology etc etc. Look at the Colombians, they have unconventional cleans especially the pulls, and only a few have proper jerk mechanics who if you look closely also happen to have long torso, short arms and short legs.
He leans forward to reduce the time it takes to get under the bar, because he needs to drop low enough, and push the bar high enough to have his arms lock out. His brain compensates by having him dive slightly by leaning forward to reduce the angle to catch the weight. If he had long legs it would be a nightmare for him, because he would need a wider split to get under and that would require a faster drop under the bar. Not to mention he would be more unstable due to the limbs and the joints being so far out of his center of gravity. You would then add that the longer limbed individual has to generate MORE power to lift the same weight a short limbed person would.
Notice how when he is pulling during his second pull? Notice the arm bend as the bar reaches his hip crease? He does that to elevate and get more of a second push to give him space to dive under and catch the weight. The typically built lifter has an advantage by not having to bend the arms at all through the lift, which makes it much more smooth and the transition more effective when it comes to the second pull at least.
The opposite build of CJ that had legendary success is a man by the name of Urik Vardanyan. He had long legs, short torso, and short arms pretty much like a T-Rex man lol.
It's strange to me, because CJ is built like another famous lifter called Andrei Rybakou who reached god level mastery in the snatch, but sucks at the clean and jerk due to his mechanics. Mechanics which CJ shares, but in fact is quite the opposite where he excels in the CnJ. What was funny about Andrei was he would be the last to win the snatch and on occasion would be one of the the first to start out in the clean and jerk, but his snatch numbers was so far above and superior to everyone else that he can still win off the total.
The differences between the lifters illustrated in my opinion has to do with muscle origins and insertions, and the way the nervous system favors certain muscle groups, like posterior chain of the body or anterior as in the quads. CJ is quad dominant, and guys like Andrew and Urik or posterior dominant.