the magic trick is that you can't "see" the rotor move with the timing light
since the mech adv can't possibly physically move the cap the rotor/reluctor have to move to change the timing...the msd link states it and shows it, the distributor machine will show it too. but the timing light probably doens't show it and that's gonna be the point RR sticks too...
I agree 100%... we know it moves but the light will say different since it flashes in sinc with the terminal(the light is on the plug wire).. but no ones wants to believe that video.. but it clearly shows it EDIT Thats why we used a strobe light to see the rotor and to see the rpm when it started to move and the top rpm when the mech was at full advance.. thats how we set up the springs and weight amounts back when I tested that junk