Rocker arms for 408 build

I appreciate your input. So you're saying the pedestal adds strength over studs and polylocks. Makes sense.
I suspect a 5/16 bolt through a pedestal never breaks, and has less flex thana 5/16 stud.
Yes, you are on the right track. The strain (in the strict engineering sense of the word) peaks up just above the radius of the nut at the bottom of the stud, and the flexing and fatigue concentrates there. With the pedestal, the pedestal has to first stretch the bolt some in order to tip up off of the head and then flex the bolt. So the bolt is loaded mostly in straight tension with the pedestals, which is stronger.

The girdle helps spread the flexing load on each stud to the adjacent studs.

Ford had pedestals in the Cleveland engines in the early 70's and they could take a pretty good beating once you replaced the factory AL ones with steel ones.