Batling Nelson and Ad Wolgost(sp) both relyed on there ability to out last there opponents when they met in the ring Ad became the only man to outlast Nelson
joe frazier stamina was utterly amazing, he wasent just constantly throwing punches but he was constantly bobbing and weaving. he was even bobbing in weaving outside of punch range. constanly moving, never clinching and always loading up his left hook. holyfeild when he went against qawi was a virtually impossible pace. so much so that qawi to this day feels that holyfeild had and a "edge".
Additionally to the alreadfy mentioned, what about Sullivan? Mcvey? Jeanette? I think the old-timers edge the fighters who fought under the 12/15 round limit also you possibly could make the argument the modern boxers had the higher workrate.
tito never had a great workrate like armstong armstrong is the man during fights limited to a certain amount of rounds