this might be a stupid question but (no pun intended)
will 2x 4lbs butts take the same time (smoked at same time of course) as 1x 4lbs butt or same time as one 8lbs butt?
Two 4 pounders will take a little longer than 1 butt @ 4 pounds, but nowhere near as long as an 8 pounder.
Two 4 pounders will give you more tasty bark than one 8 pounder.
Indeed. And the additional bark will make for some tasty eats.