I'm mainly a sweater knitter, and a lot of sweaters use the K2 P2 ribbing to finish necklines, armholes, sleeve openings, and front bands. I like the K2 P2 ribbing, but I was always trying to get the perfect tension while binding off. Usually I end up using a needle size that is 2 sizes larger but that's not always the best tension because it depends upon the actual needle sizes. Also, I don't really like the look of looser stitches on the bind-off.
I tried the popular Jenny's super stretchy bind-off, but I don't like the big bump caused by the yarnover, and I found it too stretchy for ribbed necklines and such, since they don't need to stretch as much as socks do. Here's a swatch of the bind-off for just knit stitches, and you can see the bumps at the top.
I knew that I needed to add more yarn to the bind-off row to give it stretchiness, so I decided to just try doing a Kf&b, because that almost doubles the yarn length. It does have a thicker look on that last bind-off row, but it's not that bad, and it stretches about the same as Jenny's bind-off if I do it on every stitch.
So then I decided to try it with every other stitch, and I found that the stretchiness is just about right. The stitches with the Kf&b don't look that different from the stitches with a K only. I used a cable cast-on for the swatch, and this stretches about the same as the cast-on.
So, for K2 P2, I do Kf&b for just the knit stitches when binding off, and I've found that it always gives me just the right amount of stretch. It does not look that different from a normal bind-off in ribbing.