Awhile ago there was discussion about adding a cove stripe to an A/C. On the Good Old Boat site you'll find a group of photos arranged alphabetically for a great reference.
http://www.goodoldboat.com/
Take the lefthand column down to "boat identifiers" and the "cove stripe" page should appear.
If you were looking for a parameter there are Albergs, Pearsons and CDs represented.
I've seen Ariels and Commanders with cove stripes. I wonder if any left the factory that way?
The Ariel sail plan page from the Manual I have enlarged on the wall behind the computer here has a plain, unadorned cove stripe inked in.
ebb,
My boat certainly didn't have a factory original. But i saw the same stripe on the sail plan-- thought about it, and added one after the re-paint last year. Folks who have seen the "with" and "without" all prefer the boat with the stripe. Its only 1/4", but shows up fine on dark hull.