I use a caliper to measure when I do it. If what you do works I would stay with it.
Can you explain how you measure it with your calipers?
JMHO: Which pistol slide may matter, but with CZ 75s the lined top riddge on the slide gives a good guide. No matter what pistol, the final centering needs to be at a range. The sight needs to be aligned to the bbl in the locking lugs. The slide may or may not be perfectly aligned.
Makes sense. I know slides won't be perfectly symmetrical over centered over the barrel or whatever geometry is at work here. Right now, I'm working on my P-01. Has the stock sights. I have shot a few hundred rounds through it on two separate visits to the range. I'm consistently hitting groups slightly to the left of my POA. Maybe 1/2" mean difference. I had one of the RO's shoot it and he also had the same POI for his grouping. I took a measurement of the rear sight in reference to the center of the slide and it seems to be a few mm drifted to the left.
I just ordered a sight pusher because fine tuning sights by tapping them has almost driven me insane in the past. I'm gonna bring the pusher with me to the range but I'd like to try shifting it to center first to get a better starting point.
Does this make sense? I'm no gunsmith. Only been a gun owner for about a year and half. But I always tinker with everything and am pretty good at wrenching on stuff. Which has also taught me to ask people with experience because there is always an easy(ier) way and a hard way. LOL And the easy way isn't always intuitive.