Not 100% on the understanding, no. But you guys are helping that.
To measure the cam, I used a piston stop to verify TDC on the balancer was correct. Then I made a 360 degree timing tape on the computer and attached that to the circumference of the balancer. Then I removed the valve cover and rocker arms and attached a dial indicator to measure lift from #1 intake and exhaust lifters (pushrod was temporarily replaced with a carbide pilot to keep the indicator centered). Everything was pretty rigid. I measured both lobes twice. Everything was repeatable to within 1 degree and 0.001.