THE SET'S THE THING : 'Thoroughly Modern Millie' & 'Fortune's Fool'.

What child is here," the sixteenth-century poet Sir Philip Sidney wondered in a moment of theater-related skepticism, "that, coming to a play and seeing 'Thebes' written in great letters on an old door, does believe that it is Thebes?"

Less-is-more set design, it seems, had no fan in the Elizabethan sonneteer. Had Sidney lived Methuselah-like through the centuries, instead of keeling over in battle in 1586, he might well have delighted in the more elaborate sets of a later era--the kind of meticulous constructions that occasionally spark applause and that illustrate the…