Thanks very much for all the knowledgeable responses. The bike is being built up and in spite of Road Fan's very accurate rendering of Campy's chronology and specifications with respect to the release of the medium cage RD, I am going to give the medium cage RD a shot with the 12-30 cassette. I won't come anywhere near the small small combo that dddd mentions so that should not pose a problem. And I am hoping I don't have to fudge desired wheel placement in the dropout as T-Mar suggested.

I also wanted to mention that I posted this same thread on the Mechanics forum (after all I think this qualifies as mechanics) and I received a few responses but nowhere near the detailed and thoughtful analysis that I received here. Many thanks!