We are on the same page, you just said it way better.
One turn is 5700rpm on his bike, with that oil, at normal temp. It was the best rpm for his setup. Take the same bike and put a FMF or PT pipe on and one turn will not dyno well. In short it's not a good idea just to count turns. Clean the PV window, get a induction tach and set it to close by rpm. As a base, I'd close the PV on low rpm pipes at 4000rpm and high rpm pipes at 5500rpm. Fine tune from that.