That's a useful search engine. In the Courtesy Flags thread that it also finds, Sgeir mentions Loch Spelve in his TIC post and I post later. I'm a bit blinkered by google I guess.
Interesting that even although my username was different at the time of the Loch Spelve enquiry it has clearly been able to refine the search with "silkie" since if you just enter "spelve ybw" you get the thread I was looking for, another thread (bit of a favourite Patrick? ) and a page from Webcraft's Atlantic blog where he mentions Loch Spelve and the YBW forums.