Wow, that's odd. No, sorry, I've never had that happen nor heard of it from any of my cycling friends, either. I've cycled in all kinds of conditions for varying lengths of time and never encountered anything like that. My first pair of Sidis really was too small (everyone told me they should be "snug" and, as a newbie, I bought too small), and I had toe pain but they never changed colors on me!

You did the New Bern ride? I think I saw it in another post.