They 100% left horsepower on the table. They also picked iron magnum heads, and decided to use a 1 5/8 header in a dyno competition?
I'm simply providing a data point, much as you are. Mine is however, what I have seen on a 480 hp 408 with my own eyes, with an True "A,B" comparison.
In this article with 323 cid engine, no "A, B" comparison was done.
I could throw an rpm airgap on my personal 600 HP sb engine, and it'd choke down to 550. Does that make the airgap a good choice because it made 550? No. it means I should put the victor back on it and make 600 again.
Does that make the victor an answer for a 318? No.
I very clearly give examples and conjecture that smaller, or more mild engines will respond differently, and simply won't care nearly as much. I don't understand the need to quote me every time I give my first hand experience on the topic.