When you read a thread the "post reply" and "start new thread are to close together! I keep hitting "start new thread" instead of "post reply"! (Not sure if that's what it says on the buttons, can't remember . But you get the idea )
Umm seems like i forgot that .
My suggestion: Switch the two buttons around or remove the "New Thread" button when reading a post, so it's visible only in the forum index.