I couldn't agree more on your comments. I read all of the way through, which is a rare thing on some of these boards, unless you're trying to find that one solution to that weird problem you're having!
My two cents on the Elizabeth v. Joseph debate '13 is that Moodle has improved tremendously since 1.9 (when I first became involved with Moodle). I love the new Assignment and the new Question Bank, just to name two commonly used and much improved elements, and I commend all who contributed to those improvements. As a user, not a coder, my desire is for similar types of improvements to be made to other elements of Moodle. I think that's a contender for "obvious statement of the year," and exactly how those "types of improvements" pan out is the soil many arguments grow from. So when Elizabeth proposes certain things, I think it's an example of the latter situation, not the former.
I think the most valuable thing out of the whole thing was that Joseph and Tim both chimed in to say that Lessons should use the QB.
As a user I love the Question Bank. Yes, it can be clunky, and to be truly useful you needed to do a little work (the "Question Sharer" role of lore -- http://docs.moodle.org/24/en/How_to_let_teachers_share_questions_between_courses), not to mention the learning curve, but in the end, I think it's better than the alternative, which is where every activity that wants to give a student a prompt and a way for them to input some data (by definition, "a question") does that in its own unique way.
So when Elizabeth says something like "Ideally, I'd like to see Lesson, Questionnaire, and Quiz integrated," I don't leap to the conclusion that she means integrating the actual Activities, but that instead that all of these Activities (which may differ based on WHY you're asking the questions, or WHAT TYPE of question you're asking, or how you want to govern student behavior, or your goals as an instrurutor) have access to a single resource where ALL QUESTIONS live, ie the legendary, guaranteed to be supported ad infinitum Question Bank.
I see no functional difference between survey type questions and "questions that have right answers" that would prevent the former's inclusion into the Question Bank. Consequently, I disagree entirely with Joseph's statement above that "It seems obvious that those are totally different, non-interchangeable kinds of questions. It would not make any sense to ask the Quiz questions in a Questionnaire or vice-versa. Hence the idea to keep in the Questions bank those two kinds of questions so they could be used in either activity does not make sense either."
Just because two types of questions might have different goals, or might not be used interchangeably in the same activity does not, in my mind, mean that they should not be stored or managed in the same way in Moodle. Joseph's arbitrary distinction between question types (or "functional fundamentalism" as Isabelle refers to it) serves no true FUNCTIONAL purpose, except to LIMIT functionality! I would suggest a thought experiment -- what would be gained by creating what Joseph is resisting, and what would be lost? The scales do not lie.
Furthermore, as Tim says, the QB makes a great "lego brick" to build new Activities. His Practice module is a great example. I proposed, at one point, an "interactive book" which would replace the Lesson module (which I harp on endlessly because of its problems...anyway, don't get me started...), which looked just like the Book Resource, except you could add "Question Pages" which would look just like one page from a Quiz and allow you to import 1-4 questions from the QB. Essentially, it was a slicker Lesson, without a lot of the bulkware that makes the Lesson so frustrating to use. Though, functionally, an updated Lesson Activity that made use of the QB would be just as useful.
Anyway...my two cents. They're probably irrelevant, as despite Joseph's resistance (to my reading), as I said before, both him and Tim seemed to say "yes, this would be nice, but who's going to do the actual work?" A very good question, indeed.