Jeffries style simply wont work over 10 rounds, unless he is up against sombody willing to mix it up with him.
Jeffries??:huh What a prime Jeffries?? Or an equally rusty, tired version?? Prime Jeff gives anyone a hard hard tough tough fight but Gene The Marine is still able to conduct a masterpeice Old Jeff doesn't even get close Prime Demps beats Tunney and Jeff
I have to say Tunney UD for both. Jeffries might be able to adapt to the distance in some ways but that can only be specualation from where we sit now.
Jeffries had all the physical tools as far as size strength and speed...and also had all the mental tools in toughness..however....he may have lacked some of the finer skills....ability to cut off a ring, and also headmovent (something not really brought into the modern state at heavy until dempsey). I have to say Tunney...but Jeffries would make it a fight at points.