I strongly suspect that most problems he encountered, wouldn't have happened if he had done a clean install of KDE 4.

No, KDE4 really just sucks. It was shipped out feature-incomplete, to name the most obvious problem. Apparently they decided to imitate Microsoft and have the users do the primary debugging.

Fortunately, there's nothing stopping anyone from sticking with KDE3 until they get the ugly out of 4. That's what I'm doing.