A decent flying club is a form of mentoring, because novice pilots mix with more experienced pilots.
The problem in flying clubs, which I can speak of from personal experience, is that it's allright for as long as everybody is
renting from the club (school). The moment one of the members buys his own plane, or buys a share outside the club, he finds himself excluded. So, anybody who gets really experienced will vanish, because almost nobody hangs around the self fly hire scene for long.
This is because when there is a fly-out, the school tries to set it up so that there is always a student in the LH seat and an instructor in the RH seat, so the school gets the full rental, plus the instructor rate, for every leg flown. When I was in a certain club, they were very particular about this. The people in the back could be anybody. When, as an owner, I got invited to come along, it would be only on the basis that anybody flying with me was a non-pilot and therefore no longer a potential customer for the school. Pretty soon, I was not invited anymore.
I am not making any claims for my flying skills, but I do recall that pilots who saw the way I was planning and flying, all as if IFR even if actually under VFR, and using the GPS and navaids, getting weather off the internet, etc, basically all the things which modern pilots do, they were amazed to see this and were very interested. They weren't getting this info from the school, which at the time was not teaching notams (or anything whatsoever that comes via the internet) and not teaching what to do with the red lever... If these suspect procedures got back to their instructors, it would have p1ssed them off.
Of course if you have a proper club (not a school) then it should work very well. But I don't think there are many (any?) of those. I am sure many clubs are more enlightened but this sort of self-interest does put a damper on things.
Whopity - I have always assumed you work for the CAA
I do wish the CAA released the data on this, but I am sure your 90% is spot on.