Theater of the perverse
Writing for The Guardian, Geoffrey Wheatcroft surveys the twisted world of Regieoper ("director's opera"), in which "there is no stage direction however simple, or musical sense however clear, that some director somewhere can't ignore it," and offers examples of directors' abuses ranging from the laughable to the barf-inducing:
http://www.guardian.co.uk/commentisfree/2009/jul/01/falstaff-opera-regieoper
Wheatcroft, alas, is an aging Brit, a perfect foil for the kind of director who likes to confront or confound the opera audience.