question is who is greatest not who was the best in both division and when we ask that question than i would agree with you that dc is ahead but i would put bj penn First. he was a legitimate champ in both division didnt defend the WW belt but did comeback to it and fought the top of the division and was the goat LW until khabib.
DC was a great fighter but has some *on both his title reign his HW win against stipe is highly controversial with the outragious eye poke right before the finish and defending against lewis is not a great quality defense. And his LHW title is shadowed by jones.
so I would actually put DC under Penn, Cejudo, Nunes and Couture