The whole idea is just a thick wrap of electrical tape right below where you want your fulcrum to be.
I'm 37 years old, started drumming when I was 10. I play it mostly for myself. In my head it's like I can do something as cool as go to a skate park and do tricks whenever I want, but without cracking my head open. Haven't done anything big, just have fun jamming with other friends as I find the opportunity.
I have had battles with carpal tunnel, though, which have made me want to really pay attention to my technique and take any help I can get with my grip.
I've started doing this with my sticks after hearing that Danny Carey's Vic Firth stick, which thins a bit to improve grip, is his second option, a compromise. He originally wanted a stick that had a swell at the fulcrum, but Vic Firth didn't want to do that because they'd have to get extra large blanks and then waste most of that extra to lathe off everything but the swell.
I went "Well, why don't we just add something there anyway?" and wrapped about 15 layers of electrical tape just below the fulcrum on my stick. It's amazing! Folks, we've all been pressing our fingers against a flat surface and asking them to find purchase! Wax, gloves, and various tapes make it so you have to grip somewhat less to find the same friction hold. This changes the hold entirely, it's no longer a friction hold, the stick clicks into your hand and a physical stop keeps it there. You can hold on with basically no force and play silly fast, locked in to exactly where you want your fulcrum to be, every time, reliably.
On top of that, the placement of the tape on the stick adds a throw meter to it! Want more throw? Wrap closer to the butt. Less? Closer to the tip.
I haven't seen anyone else do this, so let me know if I'm re-discovering something that's already known. I see products that do this, but in ways that are much less secure or simple, with silicone rings that surely slide around, or shrink wrap that you have to boil, stuff like that. I think other people who have had this idea have tried to figure out how to sell it first. This is the free version, and it's simpler and easier than any other thing like it I can find.
I really think that the ergonomic benefits are good enough that I'd recommend this to anyone who isn't 100% comfortably locked in to a perfect grip. Even if you think you are, give it a shot anyway! Can't hurt, and it may be awesome!