replace head bolts with studs without removing head

At risk of fueling argument further, which is not my point, here's some good reading on bolts VS studs. The advantage of studs isn't MORE clamping force, but more EVEN clamping force, since studs only see stretch and no twist. I believe that's what our friend from down under was trying to convey.

Engine studs: Understanding the advantages of using studs vs. bolts, and tips on achieving proper clamping loads