Alain Ducasse is one of those celebrity chef names whispered in hushed tones of reverence (or screamed through a gold bullhorn of marketing exuberance, if you do PR for Adour). People talk about Adour, Ducasse’s first Washington, DC outpost, based in the St Regis Washington hotel, in more down-to-earth terms: good. Very good. Really good. Great? That’s getting there.