I would stick to 3/4” holes and shafts. My hold fasts are both the Gramercy and the Veritas screw downs, and both perform superbly well in my 3 1/2” thick European Oak bench top.
Here is a video I made of how easy it is to use the Gramercy (recommended viewing for the insomniacs amongst us) …
https://m.youtube.com/watch?v=OaI_E2Yv1O0&pp=sAQA
The advantage of a 3/4” hole is that it opens up the door to many choices. I’ve never seen an advantage in a 1” shaft as I am not a reenactor nor have the desire to clamp a tree to my bench.
Regards from Perth
Derek