Kelsey Hayes longer wheel studs

The end of the knurling on the OE studs is almost exactly 20mm, the rest is shoulder. I'm thinking it would be OK since there is nothing grabbing beyond the end of the knurling anyway.

My only concern is that the end of the shoulder somehow positively locates the rotor surface. So theoretically if the shoulder was shorter there may be a slight void (less surface contact area) where the rotor bore makes contact with the stud. But if that is the case, why does the knurl end before the end of the shoulder?

Hoping someone can give a definitive answer on this. Seems crazy to spend so much time and thought on this but it is a legitimate issue for those running small bolt brakes.