Interesting to learn of your experiences.
I have never, personally, come across anyone who has lectured at a FI test on anything other than aviation subjects related to the test they were taking.
I understand the comments in respect to lecturing generally and, in business, I have given presentations on subjects not relating directly to my role as a part of management training seminars and the like. So I appreciate this aspect of your arguments. But these seminars have been designed to develop my ability as a manager and not specifically related to my profession.
Now whilst there is obviously an analogy with the FI test, because that test is designed to test your knowledge of subjects studied at the conclusion of the FI course, I have not come across anyone who has (dared?!) to lecture on a subject not directly related to the course.
This is naturally my own experience and that of other instructors I have met. The principle of lecturing on any subject is not lost on me, just that it seems too remote when the lecture is in respect of a specific qualification and not a general course of training or development.
KR
FOK