Speedmaster head hypothetical
I can't find it but I have post it before, forget what class but they had like a 162 cc limit with stock j heads and something like 370 spinning 7500+ rpm , to go faster obviously they needed more port volume but they couldn't so they lowered the flow (lowered the velocity 330 to 320) and gained hp by quite a bit and set records.
So if were not pushing these ports near there velocity limits B probably win every time but I could imagine A could be better in some applications.