I like to get a good stretch on bench, full rom. But, my training partner who is 6'7"+ tall with even longer arms proportionally, goes down to where his upper arm is just below parallel with the floor. A lot of shorter stockier guys don't even do that lowering the bar all the way to their chest! So, in that way, he is still getting a full rom for him.
Also, imo, anyone who does 9+ sets of biceps work is flogging a dead horse after the 5 or 6th set. Heavy chins and rows will do a lot of bicep work. So, if you are doing 15 sets for back (which I can understand), and then 9 sets for biceps, it's like doing, say, 12 sets for biceps in the end- if that makes sense. I guess I'm just a moderate all the way around. But, in the end, I guess whatever works for you works. I think it can take years of trial and error to figure out all angles- unless you are Trey Brewer or someone like that. That guy has more muscle fibers in his leg than I do on my whole frame...