OML before the Gorgon arc --- before he lost his right hand and its set of claws, before his eye got messed up and before he started relying on the Regenix drug, which devastated his system and ruined his natural healing factor.
Didn’t ultimate wolverine have an even more advanced healing factor than 616 wolverine? I seem to remember him talking to nick fury as a severed head. He might not even need to breath.
Plus ultimate wolverine is taller and has a longer reach.
That ability was explored in one book, yes. Ultimate Wolverine vs. Hulk mini-series.
It wasn't so much about healing; the writer was actually trying to retcon Ult. Wolverine's mutant power into being more about the survival and adapting, rather than just regeneration.
Anyway, it's meaningless in a forum scenario, as a knockout still counts as a win here.