I agree with a lot of what you are saying, threadstarter.
However, let's think about it for awhile; the level you are analyzing this at is far beyond what would be expected for a PPL or CPL candidate, at least in the US. By all means; we must all seek to increase our knowledege, but let's keep in mind to whom we will be teaching this.
Lift and other aerodynamic principles can be very hard to visualize, especially for beginning students. It is important for us as CFIs to be able to make the students learn something sensible - and although we need to be conscious about not teaching something that's blatanty wrong - imho we are allowed to, and need to, make simplifications.
Also, as far as effective questioning goes, it's not written in stone anywhere that one answer has to be 100% correct, and the distractors 100% wrong. It is sufficient to have one answer
better than, more complete than, or more appropriate than the distractors. This adds a certain level of discrimination to the test. Our primary focus when developing such tests are to make sure that any knowledgeable person will pick the correct answer, whilst making the distractors a feasible choice for the ignorant.
Let's give an example:
An aircraft wing is designed to produce lift resulting from:
A) negative air pressure below the wing's surface and positive air pressure above the wing's surface;
B) positive air pressure below the wing's surface and negative air pressure above the wing's surface;
C) a larger center of pressure above the wing's surface and a lower center of pressure below the wing's surface.
FAA Answer (according to Gleim) = B
Correct answer = C. Newtonian (Impact) Lift theory is the only case in which a net positive air pressure (i.e. greater than atmospheric) can exist below a flat plate wing. An aircraft wing (aerofoil) develops negative air pressure above AND below the wing.
Answer C talks about "larger" and "lower" center of pressures. At least to me, that does not make any sense. It sounds very scientifical, but to my knowledge, the CP is the point at where the total aerodynamic force can be said to be accumulated. While as incorrect as saying that all mass of an aircraft is located in is center of gravity, it does serve a purpose. To look beyond the scientific details, however, if we look at the big picture, lift is primarily created by a pressure differential between the upper and lower surface of the wing; correct? While none of the answers are a complete and correct explanation, answer B is the most correct. Mind you also, the question stem specifies "an aircraft wing", which is not a flat plate.
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As far as professional development is concerned, this is excellent reading for a ATPL student, CFI or whoever is beyond the basics. Let's just keep in mind that most students will be entirely satisfied with just keeping the blue side up, and we must be take great care in not scaring them away by theoretisizing too much about something which is really beyond our, and their, control, anyway.
Just my two cents.