Ouch. That's rather a crass thing to say, isn't it? He's still writing, and his stroke was at least two years ago--hell, there's a new book already out, isn't there?
Oh no, I'd heard, I just thought it was a strange way to say it.... He said it had something to do with his stroke, I remember, and he also said he is still going to write, and that's just what he's doing. Making Money is the new book, bringing back characters from Going Postal. Not only is he writing, but he's expanding the Discworld.
And I know I am seriously tact-challenged, it wasn't meant to be crude.