@SRLevine @helenclayton Lots of good answers here already that I'll have to read in more detail later, but yes - I made fenders with integrated skirt guards this winter out of old plastic campaign signs.
Between those and the low frame of my bike, I can ride with no problem in skirts and dresses that fall to mid-calf, even if they have a lot of fullness to them. I rarely wear anything longer than that, but when I do I'll usually tie a knot in the fabric or gather it up with a hair scrunchie to ensure that it doesn't get into the chain.
I don't have a photo handy at the moment; sorry!
