Quote Originally Posted by Redwoood
I never understood that. I like to think that the abrasive material from the hone and the metal particles that have been abraded away could still be present on the razor. And I don't want that stuff to get on my leather strop. So I strop on the linen side to 'clean' it. Of course those particles would now be embedded on the linen side, but I guess linen can be washed.
That's certainly a good point, but you don't have to use the linnen to do that cleaning. You should be able to clean well enough with a towel to protect the leather.

So what's the reasoning behind not using the linen side after honing?
My guess is it might be rough enough to slightly dull a new edge.

the reason for testing the razor after stropping it may be because stropping aligns the burr. I don't think you can create a blade with such a thin/acute edge without creating a somewhat instable edge. What we try to do is minimize the burr when honing, but imho you can't eliminate it completely. So just like steeling a kitchen knife, stropping aligns the small burr, which is what actually cuts through the whiskers. Now, this is not a huge thing, flip flopping back and forth, but it does get bent when it contacts the whiskers. Hence, we need to strop again to realign it and that's when you can only feel the real sharpness of your edge.
If you're talking about a wire edge, you're supposed to strop so as not to get one. That doesn't mean that you couldn't have a non-wire edge that's just too weak for your beard. But I think that it's pretty well accepted that stropping realigns the microserrations. They're on a much smaller scale than a burr. In fact, you can see a wire edge in a microscope, but I can't see microserrations even at 250x, which is the best I can get. I know they're there because I've seen them in electron microscope shots.