Not at all as far as I can see. Tunney was a backfoot fighter at HW who rellied on slashing, accurate punching when drawn into the danger zone. Holmes is a sort of technical stylist who uses the jab as his primary weapon, arguably it's his Sunday punch. Which elements are you most interested in?
I agree with McGrain. Both were master boxers, but Tunney seemed more of a backfooted-dancer type if you will. Holmes could fight off the backfoot, but had no trouble going forward and often sat down on his punches try to knock the other guys' head off.
