I think this is a bit different. Compared to this situation, Clive James was basically just being a bit of a drama queen because he has a lung condition. I seem to remember his agent or someone like that even saying (shortly after "Clive James: I'm dying" became a media thing) that he'll be around for a while (although we'll see obviously).
With Banks we're talking about end-stage cancer. And he's quoting his doctors. Let's give the NHS some credit. If there's one thing they understand, it's death.
I agree and was just playing Devil's advocate. Iain Banks is not usually one for seeking our media attention for his private life and so I have no reason to doubt his sincerity.
However if we get on to discussing the merits of his books I may have to be less generous.