Being a machinist I use dial indicators, dial calipers, micrometers, adjustable parallels, key stock, etc. to set up my tooling. It is second nature to me. I like repeatability. To some it my seem like overkill. It is just how I was taught. My thanks to all of the great craftsmen that I have worked with.
When I set up my EZ Pro dovetail jig for the first time I used an adjustable parallel to set the bit height, and the fence height. I made the cut. Perfect the first time. Instead of making a test cut and adjusting until I got it right, I got it right, then I cut.
Precision measuring tools do not lie.
Thanks to everyone for all of the helpful posting. I always learn something new.