Ha, I was going to comment on your dilemma, then realized the link pointed to my post a while back. Too funny. In addition to using the Clamping feature, I also had some IOR settings set to astronomical numbers. That was based on an old tutorial I followed. Not sure if this is mentioned in my old thread or not. You have to be careful with the Clamp setting though. You can remove too much of the highlights if you're not careful.
I also remember something about using an HDR vs. just a Sun and Sky object. Good luck.