The answer is that it is reactive, neither the database providers nor the schools can anticipate the direction the exams will take because (1) the syllabus we have been given is so badly written almost anything can be asked (2) the questions being created are in a large part not properly validated.
Once the questions appear we can modify our feedback. An example is Op Procedures where improved feedback was allowing passes on the new material within two weeks. In some subjects feedback is very difficult to get right because the questions themselves are wordy and complex (Air Law), in other subjects it is relatively easy to get right.
The situation is not helped by the poor english of the examiners, by inconsistent use of reference documents, by questions with answers that are just plain wrong and by the exam authorities bending over backwards to avoid crediting exams, which means defective questions are not removed.
All in all it is a shambles, and the JAA and EASA have been trying to get this right for 15 years. It is unfair on the candidates that have to sit these new exams. EASA and the CAA say that the new questions are an effort to stop people relying on question banks. The paradox is that the effect of their poor quality of work is exactly the opposite of their intentions.
Very few people complain because there is a feeling that the regulator will 'black spot' you if you do. There is no quality system that applies to the exams, no external regulation either. Even the schools are reluctant to complain and be seen as 'trouble causers'. To paraphrase Juvenal, who will regulate the regulator?