I finally quit using my Park Tool chain checker and tried the ruler method on a customer's bike
Had a guy bring in a Trek from 2019 with a skipping chain and I checked it with my Park Tool CC-3.2 first. It read 0.5 percent wear so I almost told him the chain was fine, but something felt off. Grabbed a 12 inch ruler instead and measured pin to pin, and it was actually past 0.75, chain was toast. How many of you have switched off the go/no-go gauges for the ruler method?