Using your past comments about the Tohuku quake, specifically that Japan should have known that such a large quake was possible because there was evidence of them having occurred in the past, is there any evidence of such large quakes on the San Andreas? I'm not aware of any.

Doesn't mean it can't happen, though. Just that no evidence has been found.

On the other hand, I've heard many times about it being 'impossible' for the SA to rupture form stem to stern because of various things, specifically discontinuities in the fault and the likely inability of a fault rupture to propagate beyond them.

Then, going the other way, the Landers quake showed that large quakes can occur involving multiple faults thought to be separate.

I guess this just shows we don't know Jack, eh?

Brian