I wasn't flying back then but I gather that the PPL/IR takeup was greater say 10-20 years ago, due to other routes available around the ground school.
I vaguely recall (perhaps somebody can fill in details) that if you had 700hrs total time you could skip the ground school and just turn up for the exams.
If you look at any group of non-FAA PPL/IR pilots today, you find that nearly all of them did their IR many years ago.
DFC - can you supply a reference for the Class 1 audiogram (with the current JAA limits tested at four frequencies, in each ear separately) being ICAO for all IR?
Somehow I doubt it, because the CAA is already known for having recently allowed an IR to be awarded to somebody who failed the initial but passed the renewal limits - this is exactly their 2005 proposal as it happens - provided he did the whole IR first and passed it. A rather onerous way to do it I think, especially as you do the exams and the flying and they could have refused........
The comment about somebody having done both doesn't really apply because nobody will do both in full unless they are a masochist. You always do a conversion. The JAA to FAA one is easy - the FAA doesn't have the protectionist issues to worry about. The FAA to JAA is a lot harder but you still skip most of the flight training requirement.