[left: One can see how thin and frail Kim Jong-il looks in this KCNA file photo of the Dear Leader turning off the lights in his office. Contrast that with his porcine and vibrant visage from his 2005 album cover (below).]
Strokes caused by blood clots are like being shot with a bullet: Like bullets, the same blood clot doesn't attack you twice (except for that nasty bullet that shot JFK several times), so once you've survived its effects then you only need worry about the next one coming. No doubt the Dear Leader probably is imbibing more Coumadin than cognac these days, lest he get another stroke that could off him completely.
I'm not saying I don't believe the pancreatic story, only that we've seen so many speculations passed off as reliable (or rather, as reliable as we have at the moment), yet he's still here. I think the stroke he likely suffered last year has piqued the global media enough that they are looking for medical problems to pin on him. It's almost as if they are trying to will him into the grave with their reports of his bad health. (And while that would be a silly expectation to have, I think the reports could will people into being better prepared for his death.)