I recently commented that my first fair-isle sock heel flap had abnormally large pickup loops? I figured out why. I was doing a salt-and-pepper heel, and the yarn that was included as part of the slipped stitch on either end also included the small float. So when I went to pick these stitches up, the floats pulled through and I ended up with abhorrently large pick up loops. The remedy, I think, is to stop the salt-and-pepper coloring a few stitches before the end so that you don't get a float in there as part of your slipped stitch.
There were almost no guidelines about how to do a salt-and-pepper heel flap on the cyberclass web site, and I was unable to find a whole lot of suggestions on the web relating to this issue. So my recommendation, if you're going to do a salt-and-pepper heel flap, would be to always make sure that there are at least 2 stitches of the same color on either end of the flap rows. That way, the heel flap pick up should behave as with any other heel flap. Perhaps another way would be to tack down the float behind the second to last stitch, but I don't know if that would work as well.
So, the result is that I will have slightly fraternal socks... but oh well. It's not a big deal. :)