He was wrong about the 40D and the 7D, and it\'s pretty clear that he was using the wrong AF Custom Function for most of the test shots he took with the Mk IV - Main Focus Point priority is specifically designed to track any new high contrast object that crosses selected focus points, which is not what you want in the shots he\'s posted as examples of poor AF.
Canon\'s AF user guide is pretty specific about this.
I reserve the right to be skeptical about RG\'s \"findings\"...
