It limits the rotations/spin on the disc I think

I get a cleaner release with my finger on the rim right on the parting line. Always open to try new ideas but then use whatever works best for me.

you can try it yourself and see how it changes the spin of the disc, in my experience with it because directly on the spine of the rim it gives you no ability to stabilize the torque you are putting into the disc so you get a common off axis torque wobble (like Ohn Scoggins putt) if you can make that work consistently then its fine, but its going to be a harder to control putt.

​@@brekkohit sounds like it makes sense but is this a theorie or has it been shown in slowmotion or something. I keep my ibex give on the rim and I can't say I have any more or less wobble it spinn then anyone else.

Imo, it allows for a clean release. The leading edge of the disc should be unimpeded by your finger as you release it.