Hi Daw! I don't mind you chiming in at all - I'm very grateful, for advice and sympathetic noises both! :-)

I eventually intuited towards the reverse funnel, and I've got what I think is a pretty solid conclusion now (it had better be, I'm submitting it later today!). The book on "Genre Analysis" sounds fascinating; right up my street.

Interesting to read that your research is with engineers; I teach organizational sociology to undergraduate engineers and find them very challenging and rewarding students.

Thank you again!