Seems to me in the race car is about as good as it gets for real world testing.
If a modification allows / requires you to pull nearly 10% of your total timing, I'd figure - that in real world terms, that was a big deal.
Very very few developments results in "big" gains.
I've asked this before, but has anyone ever heard of John Flinchbaugh? He was patenting a piston treatment which reduced timing a full 30% as a result of accelerating the combusrion process - in chamber. John passed away before he finished testing, and I've yet to evaluate it for myself.
P.S., you can do something right with one thing, and scr*w it all up unknowlingly with something you've done wrong with something else. Qualified testing isn't everyone's best characteristic.
Troy Patterson TMPCarbs.net