I agree. I've changed modules on my Martin and last year on my Pearsons. From 75% to 65% on my SlayR got me about 4fps. On my Pearsons I changed from 85% to 75% and then 65%. Total gain was around 4fps. Not enough to change unless I really wanted more holding weight.

That being said, if you can just change a module then it might be worth a try just to satisfy your curiosity. Modules generally cost $15 or less. Maybe you'll like a bit higher holding weight. It often promotes better accuracy giving a cleaner release.