Shortly before the 1st UFC, Royce went to Philly to roll in a challenge match with 2 brothers who were freestyle wrestlers; each weighing in at near the 4 bills mark.
The video was amazing; Royce was clearly the better technician and athlete, but was geometrically unable to put a choke on the guys...their danged necks were too thick to get an arm around! One of them, once rear-mounted, he had to go for a Japanese wristlock on. The other guy tapped out because Royce strained the dudes back jockeying for position.
Well, size matters MOST of the time. As giver and reciever of size-related BJJ whoopins...I was 6'4"", 245 when Royler mopped the flooor with me, and 215 when I mopped the floor with an old 49-er and a LA Ram.