Surveying the teaching of Q: What do you make of it?

It is unfortunate that the widely used symbol Q is employed in different senses by different writers. - C. K. Barrett

The symbol Q may still be used as a convenient description of the common material, while each investigator must be left to make clear whether he is thinking of written or oral material or a mixture of both. - Donald Guthrie

None of the arguments against the existence of Q as a single source is fully convincing. . . It is thus best to assume that Q was a single source, available in Greek and probably in written form. - Christopher M. Tuckett

What is being taught in the classroom nowadays concerning the Q hypothesis? I would like to survey here what lecturers have been teaching lately (say within the last few years) concerning Q (the hypothetical sayings collection attested in the Mt-Lk double-tradition).

From my own observation of what students are taught I can see that not much source theory actually sticks. The letter Q seems to be something that does stick, however. Presuming everything taught did stick--what exactly was it that stuck? I am presuming that what different institutions teach could be placed on a "Q-spectrum" or "Q-continuum" ranging from "pro-Q" (Q is basically reconstructable) through to "sceptical-Q" (the Mt-Lk double tradition does not derive from a single written source or "sayings collection" prior to its inclusion in Matthew).

So for those teaching/introducing the synoptic problem to students, my three questions are:

(1) Where are you on the Q-spectrum? (What do you teach students concerning the Q hypothesis?)
(2) What is your teaching style regarding the Q hypothesis? (How strictly do you teach what you teach? I.e. are students encouraged to challenge what they are taught and come to their own conclusions? How do you introduce arguments for and against?)
(3) What do you think sticks with students regarding the Q hypothesis? (How much of what is taught do most students take with them?)

Please leave responses directly here as the comments can then be easily read by all those interested.