Macintosh
Sorry I don't have an answer, but I do think you should post this on the Instructors forum as well. Now is just about the time it's all going to hot up.
The legislation seems to be a mess. The pragmatic view may well be that if an instructor is unhappy with the quality of a PPL's flying he has a responsibility to ground him.
But do the JARs intend to make evey instructor an examiner?
I hope this thread gets some serious attention.