So here is my take on the Boss Cleveland head port. Have the factory make them the size of the grand canyon, then let the racers epoxy to optimize port size. If it is a huge factory port, it's legal, yes? Most racers need to go bigger. Maybe Ford teams went smaller? I have seen many pics of heads all epoxied up raising the floor of the port.
I agree a lot of race teams did that but your average builder didn’t and the stock engine definitely didn’t and they dyno higher than any of the other muscle car small blocks with a relatively small cam.