He‘d have a ballpark idea of what he had. That’s what a caliper is good for. Quick and dirty measuring. It’s not precise.
In fact, I put all my calipers to the test in 1 inch increments. Most of them are off in at least one increment.
No one should be boring and honing a cylinder with a caliper. Or any of the **** this dude is doing.
Ring seal, bore geometry and ring technology is so far ahead of where it was even 10 short years ago it’s not funny.
Garbage is garbage. Doing it the way this guy is doing it is garbage. If he’s down with garbage then I’m good with it. Just don’t tell me how cool it is, or how revolutionary it is. It’s neither.