SS,
OK ... I'll crawl back under my rock just like a good little PPL should
From some of your comments it seems like you are the one who wants a divide between PPL and CPL pilots. know one has suggested that anyone should crawl anywhere.
I agree with you that a PPLer that wants to become instructor shoudn't need to learn about flight at FL320. Yes there is room for a stand alone exam for PPLers wishing to become instructors. I think though that the manpower to put a course together and overview the exams would mean a very expensive course for those few candidates per year that want to undergo it.
So an experienced PPL isn't likely to have expanded his/her knowledge over the years since passing their PPL? I suppose pilots of 5, 10 ... 20 or more years know little more than was required to pass their original test?
Every good aviator I know strives to learn more about aviation than they need to know. Is doing a CPL course not doing this?