When I did a search, I saw that the Advan A048 and AD07 available (outside the US) all had the "LTS" designation after it. (LTS = Lotus I'm guessing.)
This is my guess why Lotus would want to work with Yokohama on the compound (as opposed to just the tread design): The Elise is much lighter than most cars on the market. Yokohama probably had to come up with a different (softer) compound to get the tire to perform with Lotus' suspension. Too light of a car and too hard of a tire compound means that a tire won't reach it's operating temperature and offer maximum adhesion. Of course, that's just my guess.
Bob
This is my guess why Lotus would want to work with Yokohama on the compound (as opposed to just the tread design): The Elise is much lighter than most cars on the market. Yokohama probably had to come up with a different (softer) compound to get the tire to perform with Lotus' suspension. Too light of a car and too hard of a tire compound means that a tire won't reach it's operating temperature and offer maximum adhesion. Of course, that's just my guess.
Bob