And that's why I'm thinking you should bail on the cleans and squat cleans and just focus on clean pulls:
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Clean high pulls:
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Bottom position squats:
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And of course tire flip:
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(It shouldn't look that easy - he's obviously not using 80% 1RM.
)
As to why it helped his hitting power, I can guess that when you do tire flip you learn to commit fully to the movement. Because by not committing 100% you'll end up stopped at the hip and have to work it over slowly, which anyone who has done it can tell you is hell. So you learn to drive both FORWARD AND UP (something you don't do when you perform stationary oly lifts), and you have instant forward transfer with your upper body as well to finish the flip.
All I know is I'm a pretty stout 230 pounder and he was 190 and I wouldn't want to take more than a few hits from him now...
I hope this helps.