Ok, sitrep....
I tried disconnecting the MAF, but when started it ran very very rough. I plugged it back in and from cold it started Ok. Unplugged it and very rough again. Decided I couldn't risk a test drive like that because I don't know what will happen if the ECU decides that both the Crank and MAF sensor are kaput.
The new sensor arrived sometime Friday (thanks Shack) so Saturday morning I fitted it. Not as easy a job as it should be, but there are worse ones. Drove it home (14 miles) and with trepidation approached the last roundabout...and...it was Ok. Haven't done many miles in it so far, but I did go to the chip shop again this evening, and then ran my Dad home 2 hours later and it hasn't stalled yet.
Idle isn't brilliant, but Ok. I'm reluctant to declare it 'cured' given the lack of driving so far, but it's looking promising.