I'm not knocking them at all, they were very tough and skilled. Judo, I can somewhat see what you are saying as the rules of the sport have changed the way it is performed, with a decreasing value on the ground game. Catch wrestling though, has some flaws that would be hard to compensate for, mostly the favoring of a submission from anywhere as opposed to the more systematic approach of positioning improvement of modern grappling. More to the point though, the question was about Jack Dempsey's grappling skills, and the grappling skill involved in MMA today is certainly at a higher level than what Jack Dempsey had.
Well, Dempsey definitly wouldn't be winning abu dabe...but my point would be he punched hard enough to score vicious first round ko's over men who outweighed him by more then 40 pounds, fast, and very skilled (he looks sloppy when going at a hurt Willard with blood lust, every other bit of footage shows great skills.). So the question is would his ground game be enough, and if taken down, allow him a high percentage of getting back up or at least holding his man and laying and prayin till stood up. But yes, dempsey was not the best grappler of his time. Of course we have had some great mma guys who where great in one area and only so so in others.
yeah..and he could make that....he weighted about 184 for the willard fight..but that was with all his clothes on..plus he would later say some metal weights in his pockets. He was likely close to 170 when he fought willard...and with some easy drying out..he would have made that with no issue.