Originally Posted by astroflyer

Precisely, technically the exception only applies to United Clubs and US Air Clubs for UA and US *G's. They should theoretically be allowed entry into any other airline's *G lounge. This practice seems to work with LH with entry being granted at IAD and DTW. At IAD, it's out of the way for most UA flights, and DTW just doesn't seem to see that much traffic.

However, at SFO, when they opened the airside bridge between the domestic and international terminals, the SQ lounge was deluged by travelers. I did enjoy it for a period of around 6 or 7 months, but then the crackdown came once the word got too widely out. There's a lot of FT posts in the UA forum on this subject, arguing about how outrageous this was on SQ's part. However, they have to have a respectable lounge for their premium pax out of SFO, so I completely understand it.