They drew lines on the drawings of the cam profile to locate where the ramp changes.
There's a few posts on Speedtalk about this. In one someone posted (not Wyrm) finding them to equal to between .007 to .011[?] lift at the valve. Argh. can't find that post now.
Here's one with Wyrmriders explanation, top of page 2: Degreeing a camshaft for begginners - Speed Talk
I think one of the points here is that the MP advertised duration is a measurement on the cam, rather a measurement at the valve. Maybe the FSM too - need to pull one off the shelf and see how they expect the number to be used, if at all, for repair purposes. @Wyrmrider If you still have those cam doctor profiles, it would be really cool to with the FSM and Mopar performance published data.