Just thinking back... when removing the headbolts, I was surprised, after loosening them, by how few turns it took to remove them.
After reading what I could find on this site about using studs, and bottoming them out, they must be longer. Then I read about the larger diameter of the studs blocking oil flow to the rocker shafts. And studs may also cause interference with header flanges.
My thoughts about using studs are for more thread engagement deeper in the block hopefully resulting in less deck distortion. ???