Having been involved in the provision of ATPL training for a number of years, both by full time and distance learning courses, I am a firm believer in the value of consolidation training. Even with the best books in the world many students simply do not understand much of the material.
Over the years I have lost count of the number of times students have said things like "Why is it not explained so clearly in the notes" or " I have learned more in a week with you than I did in six months reading books". I do not claim that this is a reflection of my teaching skills. The fact is that it is much easier and more efficient to get complex subjects across in face to face discussions.
Having said all of that, I think we are stretching the truth a bit too far if we suggest that the JAA requirement (for at least 10% classroom training in any course) is the product of any truly logical thought process. We need only to look back to the original concept to see that this is not the case.
The original idea was that students would be required to take all 14 examinations in one sitting. It was only after protests from the schools (who were horrified at the probable effect of this on their pass rates), that the JAA relented. But even then they only relaxed the regulation sufficiently to permit the taking of all 14 exams in two sittings. This two-sitting rule is the main reason why most schools provide courses based on two modules.
After many protests and much debate the rules were again relaxed to permit students to take the exams in whatever groupings they wished. In response to this change a number of schools have switched to a three module system, which permits students to concentrate their efforts on a smaller number of subjects at any one time.
In my experience most consolidation courses are a mixture of formal training in the form of a review of the more complex aspects of the material, plus a good many practice examinations based on feedback from previous JAR exams. Most importantly, to be truly effective the process must include detailed debriefs of these practice examinations. It is this debriefing process which (done properly) enables the student to understand why an answer is correct, rather than simply learning which answers are correct.
The vast majority of students currently studying for their exams would be unable to pass most of them without the benefit of consolidation training. Even with the benefit of consolidation training a small number of students repeatedly fail some subjects. In most cases these students eventually pass only after carrying out further consolidation training, often with a school that was not their original training provider. This does not mean that the original training provider was inefficient, but simply that a change of emphasis or teaching style often makes the difference between success and failure.
Now let's get back to the original question of whether or not it is reasonable to make consolidation training compulsory. Personally I think that it is not reasonable. More importantly, it is not an effective way of ensuring that students actually understand the material they are studying.
As stated by Alex, the real problem lies in the exams. The current system uses a relatively small number of questions, most of which test knowledge of facts. The JAA should construct a proper question bank, using a very large number (tens of thousands) of questions. If these questions tested comprehension, it would be impossible for students to get through simply by learning the answers to a limited number of questions.
One school currently provides a consolidation course for a subject using approximately 185 feedback questions. The students taking this course often find that the vast majority of the questions in their subsequent JAR exam come from this list of 185. This observation is not intended as a criticism of the school in question. They have created a consolidation course that is very effective in getting students through this particular exam. But this situation clearly indicates that too few questions are currently in regular use for that subject.
The problem in setting up an improved question bank is the fact that the creation of such a system would involve a great deal of effort on the part of the JAA. But once the improved exams were set in place, students could be freed to carry out their studies in whatever manner they wished. But at the end of the day I suspect that there would still be a lot of business to be done in the provision of consolidation training.