I think a lot of guys do over heat the edge with power tools, belt sanders & etc. It's not automatic that you will. It requires a certain touch to do it consistently well and most guys do not seem to posses that artistic touch.
Edit: After reading the two following post I want to clarify when I imply most guys will screw it up, many of those guys would never visit this forum for advise. But even with those who do, there are some pretty fat fingers or something. But the two following posters sound like part of the minority that do it well.