Quote Originally Posted by Bart View Post
What I only partially buy, is that "better glide" theory.
A razor does not cut with less effort because it glides better through the whiskers. It does not need to glide through the whiskers. They're not a block of cheese where the knife needs to still pass trough after the cut.
I hate arguments by authority, but the commercial razor blade manufacturers disagree with you. The friction i'm talking about isn't the friction between the whisker and blade after the whisker has been severed - its the friction between the whisker and blade while it's still being cut, as the blade is forcing the whisker apart. The initial effort to separate the strands of fibrin is determined by the edge width, but the whisker is as much as 180 microns across, so the two halves of the whisker are riding up the bevel quite a ways, and the whisker in front of the cutting edge is being stretched as the blade is forcing the two halves apart, acting like a spring and pulling the two halves tightly against those bevels. This can cause substantial friction, and substantial resistance.


Quote Originally Posted by Bart View Post
The only glide we need is glide over the lathered skin. I don't think we are able to discern much between the different levels of polish we put on the bevel of a razor.
Of course we can. The edge doesn't get any sharper past about 4k, but the bevel gets more polished. The commercial guys stop honing at some coarse grit, but that teflon makes all the difference in the world. And schick's "making of the modern blade" article makes it clear that the do it for sharpness, not smoothness.


Quote Originally Posted by Bart View Post
I do think teflon fills the scratches, reducing jaggedness of the edge, and therefor reducing the damage to the skin. It irritates less, which also could be called "smoother".
I disagree. A few years ago after I first read the Verhoeven paper I was looking into the whole sharpness question, and trying to figure out what the commercial guys knew about it, and ran across the patent for teflon coating razor blades. That patent claimed that the teflon coating was just a few tens of nanometers thick (i.e. too thin to fill in or reduce the jagginess of anything), and that the stress of shaving caused it to peel off of the cutting edge nearly instantly. Over the course of multiple shaves the peeled area would gradually increase until it was no longer effective.