I checked out the link to that tartan... It's MacKinlay (I think... the pic isn't very clear)

http://www.tartans.scotland.net/tart...tartan_id=1313

If you pick up a tartan book, you'll notice that MANY tartans are just "a blackwatch knockoff" (although you might not want to call them that around the wrong clan). Check out Campbell, MacKenzie, Armstrong, Davidson, Farquharson, Forbes, Gordon, Keith,... the list goes on and I'm only on "K" in my book.