I have spoken with Dave this morning again. TBH, he doesn't sound his normal cheerful self at all. I can tell this has been a BIG shock to him. He is OK, but very shaken by the sound of it.
I won't give too much away here because Dave may not want me to. But I will confirm that this was the Fiat coupe he had bought for Mrs Laidback. BOTH airbags deployed. By all accounts I think he is lucky to escape with the minor injuries he has. Could have been an awful lot worse and I think that his experience behind the wheel may have given him the split second he needed to avoid this being a fatality!
In case anyone is wondering, no he didn't cause it. The cause is yet to be established, but it would seem that a major mechanical/structural failure may be to blame. The car is a total loss and is well beyond repair by any stretch of the imagination.