As ridiculous as his pre and post fight antics can be, BJ is still one of the all time greats at LW, probably the best ever. If he's in shape and motivated, I don't see Kenny winning the fight. That said, to respond to the TS's hypthesis, I do believe that BJ would take a long break at the very least if he were to lose.
Ehhhh Gomi is still the GOAT but BJ has the potential to take it from him.
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Are you trying to say Jesus Christ can't hit a curveball?