each chamber on a revolver's cylinder can vary, same for the throats, then the forcing come and endshake can cause inconsistency and/or loss of performance, then the barrel to bullet seal. with a looser bore, shakey cylinder, and oversized throats, (or just slightly undersized bullets) you lose quite a bit of pressure. I bet a revolver that is at the max on specs vs one of the exact same make that is right on the bottom side of the specs would shoot a lot different.
I know that h-110 out of a ported four inch revolver I used to own did rediculous things with 125gr bullets that no other loads could come close to. that thing tried to come out of my hands pretty regular, it was an event to watch someone else shoot it and see how high that muzzle went up in recoil. I never chronographed it, but the fireball coming out the barrel, the muzzle blast, and the exploding melons convinced me. If it didn't meet the advertised POTENTIAL then too bad, because it was still the best out there. I've shot watermelons and canteloupes from 25yds with redline .45 colt and the effects weren't much different honestly. My problem is a fear of gun abuse, h-110 will top anything else for sure, it's just a question of whether or not you're going to chew your gun up with it.... if you have a lot of expendable money to buy a new gun or two then go all out.