Speedmaster Flow Limits

Then there is the case where you get to a point where you hurt the low end lift pretty good and pick up on the high lifts pretty good. This, to me turns the head into a drag head where the valves are just simply shot open as fast as possible and then just hang out there for a spell before closing.

Not really a street head anymore at that point.

Having a nice fat curve is where it’s at and will make the most of the head in most every application.

IMO of course.
I agree, and I’ll never be able to make that distinction on the flow bench. Plenty of people with success with both the 45 and 50 degree seats. I have learned that a top cut angle of 5-10 degrees less than the seat angle helps flow in the mid to high lift zones while marginally hurting low lift flow. It also helps keep the short side flowing a little longer.