Re:
I though CDA was same pattern but Aluminium instead of chromed steel? Used to ride with a lad who had full CDA, (bought as a boxed group,) on his bike BITD and I feel sure headset was this pattern, but Aluminium cups and top nuts.
Seem to remember also, although CDA wasn't "top" of the range back then, one of it's selling points was a saving in weight?
I have a CDA mech and the same years Record and Super Record mech's are quite a bit heavier. I'm maybe wrong, but vaguely remember this was the big selling point.