I've been investigating stropping from a different aspect. I went to get strop leather from a shop that's been making hand made saddles a very long time. The saddle maker asked if I wanted 'hard or soft' because that's the way he had them sorted for sale. Large boxes of each.

I picked out some 'hard' finish because it more resembled typical strop leather. Then, I went over to the 'soft' and got some of it. Purchased by the pound, 2 bucks worth is going to be enough to make several paddles.

Anyway, the difference in draw between the various finishes is extreme. Softer finishes produce major draw with very little downward pressure. The harder finishes produce almost no draw. Neatsfoot oil or strop dressing will be required for them.

Anyway, for my two bucks, the draw or amount of friction between leather and blade is a significant factor in aligning the blade and also generating heat, perhaps as much as speed. More will be revealed when I find the microscope I'm shopping for.

FWIW, Weldon (my first barber) used to slap hell out of a hanging strop attached to the side of the chair after every haircut. That's because even a kid's cut came with mug and brush lather and straight razor neck shave. He would also hit the linen once in a while.

And yes, it was entertaining.

Regards