B767PL...
I am currently doing the JAA conversion from a Canadian commercial licence.
Obviously I do not possess the heavy time required to just sit the two exams / flight test, so am having to sit the 14 writtens plus 2 flight tests at the end of it.
Having sat the (admittedly basic, but fundamentally sufficient) Canadian CPL/ATPL exams, I have to say that for the most part, the amount of time and detail devoted to each subject as required by the JAA is laughable. It is (IMHO) a licence to print money. The only other purpose it has is as a filtration system. The subject matter is 90% surplus to realistic requirement - who cares about the trivialities of an AC electrical circuit in its minutae - a zener diode or a capcitance fuel system?! Am I really going to be repairing or discussing the intricacies of a remote indicating gyro compass, a selsyn system or gyroscopic transport wander, at the controls of an A320? - no! I was initially trained to fly and safely navigate an aircraft - not to build the bloody thing!
In answer to your question, money talks in the Euro zone. So does red tape and bums on seats in JAA headquarters being paid to administrate all the above. So its largely a case of bite the bullet, and "learn and dump" All in all, a very frustrating exercise, but a necessary evil.