bollar: Don't think it's a CAT II/III issue. I think WN's planes are CAT II equipped and SFO is very seldom at CAT III. Besides, the problem at SFO is not so much low minimums for the approaches, but reduced arrival rates any time the weather is less than VFR.
Additionally, if you look at DOT stats, WN tends to have a higher percentage of on-time arrivals than most all other carriers at SFO.
[This message has been edited by letiole (edited 01-23-2001).]