'Porgy and Bess' at National Theatre: Respectful and genuinely thrilling

The "Porgy and Bess" that's muscling into the National Theatre this week for a brief run is the same one that caused such a theater-world rumpus two years ago. That's when musical theater giant Stephen Sondheim lambasted director Diane Paulus, playwright Suzan-Lori Parks, musical adapter Diedre Murray and star Audra McDonald for changing the landmark 1935 opera to suit 21st-century Broadway standards.