If one goes into Studio 54 expecting a dusty old collection of boulevard comedies, they are in for a real surprise and a real treat. These are truly funny comedies of manners-usually bad manners-that have aged quite well, and Parker and Broderick are in top form, keeping things fresh and moving. Parker in particular gives a virtuoso comic performance. In each play, she moves easily from landing a subtle comic line to broad physical comedy to some very touching moments. And all the time, she keeps any Carrie Bradshaw mannerisms under wraps. She just has to come back to Broadway more often.