HFT vs SFT Cam Identification

Years and years, decades ago; I read that;
Solid lifter cams have two ramps; a clearance ramp and the usual acceleration ramp.
By degreeing the ramps below .050, and analyzing the data as to lift per degree/per degree/ you can find the switch point. or not. If you find it, it's a solid. If you don't, it's not.
IDK if that's true, but that's how I remember it.

The thing is, the lobes are not flat across, so IDK how accurate V-blocks would be. To find the wear on my used 340 cams, I chucked them in a lathe and rubbed the indicator down the center of the lobes.
There is a lot of tedious math involved ............