When fighting at LW, he never gassed. He went the distance 5 times at that weight and although he wasn’t able to keep up with Edgar in the rematch, he didn’t gas. He went to the 4th round against Florian and was still fresh. Took him down and choked him out. He went to the 5th round against Diego and was still fresh. Put him away. Finished Sherk and Gomi late in the third round, still not gassed. BJ has only ever gassed from fighting big WWs. So no, he would not gas against today’s LWs.