Auto-Match Banner Colors

I was recently messing around with different profile options, and noticed that the banner color used to auto-match whatever avatar picture I used. I experimented with setting colors myself, but I would like to switch back to the auto-generated colors, as it always seems to know what a good combo is. However, I can't seem to switch back once I've manually picked a color, and several sites on the internet seem to confirm that there is no way back. I would highly recommend adding this as a feature in the near future.