OMG, I am so relieved. I got it started !
Talking to a mechanic friend of a friend just about 5 minutes ago who said he'd seen this happen with 16v Mondeo's and Vectra's on occasion.
He said that sometimes, if the car has been used on a short trip and then left for a spell the hydraulic lifters can drain and stick in position. When you then spin the motor over, the valves can be left extended producing the no-compression scenario. He said that after wasting time by stripping two motors with similar symptoms, he now drags them down the road at 40mph in third which basically frees them off. Sounds pretty basic and I wasn't about to do that without first checking that the cams were at least rotating.
This sounded familiar as the last time I drove the car was 10 days ago when all I did was move it from one side of the garage to the other.
Anyway, I went down to the car with the intention of checking the cam rotation. While I had my missus craning her neck to see inside the cam cover as I turned the motor over ( Hey, I'M not getting dirty! ), I felt the motor make the tiniest of efforts to fire on probably one pot only.
Never one to give up early, I cranked that S.O.B for all it was worth. Gradually she started to pick up more and more until I had 2 pots making power, then 3, 4, 5 and YES 6 !!!!!!!
Oh Baby, I don't have to tell you guys how good that felt !!!!!