You can get up to 300 at 5'10 drug free (which is a pain in terms of food intake alone and probably not worth it for most... Drugs or no drugs, people don't usually want to go there training and diet wise, plus sleeping will likely become an issue), but obviously you'll be more than a little smooth no matter how strong. A little more smooth than just "off-season bodybuilder"... Then again, ~270+ is definitely doable if the trainee wants to go that far food and training-wise and it's roughly where I'm strongest relative to my bodyweight on the bench, for example...
I was mostly throwing the height thing in there to show how crass the difference can be in that one particular weight class and pretty much nowhere else.
Previously a tall guy, while quite possibly at a disadvantage in the bench (if we go with the tall = long arms stereotype and considering that he's not going to carry as much muscle relative to an inch of height or whatever) and possibly squat (long torso), would at least not have to compete against guys so much heavier than himself in the same damn class.
A 275 lb class tall guy with long arms at least has the deadlift going for him, usually, to sort of even things out compared to a 275 lb class shorter guy, and he wouldn't have to compete against 300 lb guys.
Most shorter guys in his class would be around 243-255 or something like that, he'd likely be more along the lines of 265+... Which originally helped even things out, but will now lump him in with the REALLY big and strong people.
It's all hypothetical of course and depends on the individual lifters (there are tall freaks weighing 275 who outdo most shorter guys outweighing them by 20+ lbs, but that's the exception to the rule imo), but I still think that the upper end is way too open, and lots of taller guys will have to be in that class if they want to really maximize their relative strength and go after records (except maybe on the deadlift), or even if they just want really big lifts and pack some serious muscle-mass or whatever (which can be a little hard in the 242's and 220's for a really tall guy I'd say).
Oh well, people will adapt and all, but I just don't see why it was necessary...