I know from the hurricane thread, GB, that you're going to stand your ground like Charles Barkley in the low post wearing a lead vest. So this will be more for the benefit of the house:
I think I've been misunderstood a bit. I was making the point that Twix never had the chance to become "classic" in the U.S. until it was sold in the U.S. (1979). Therefore, IMHO, it's fair game to start Twix's clock at 1979, and not start it's clock then the Raider bar was developed in the U.K. (1967). Don't really care that Raider and Twix were pretty much the same thing -- to me, wide availability in the U.S. is integral to "classic-ness" as evaluated by a bunch of American guys on a web forum.
I also find it telling (and I'm thinking that you won't agree) that Raider changed it's name in the U.K. to Twix in 1986. The Raider was "just a bar", but the Twix was what became classic -- and then, the namesake of the Raider.