Stephen Sondheim's epic burn on the "Porgy and Bess" production being helmed by Diane Paulus with new material by Suzan Lori-Parks raises some natural pushback about whether Sondheim is getting behind excessive traditionalism here. So it seems appropriate to reiterate what is cool and what is not cool when producing new versions of old plays:
1. Productions supplying an existing text/score with stage business that radically departs from the traditional production: COOL. Here's the space for your Regietheater, your modern dress productions, your severe minimalism--you don't have to like it, but this is a valid way to present an existing play in a new light, draw new inferences, keep things fresh. As long as you allow some leeway with stage directions, there's really no theoretical daylight between a "traditional" version produced 100 years after the fact and a "nontraditional" version.
2. Productions that add/subtract elements of the body of existing text in an attempt to get closer to what they believe is an authoritative/performance friendly version: COOL. Yes, this gets tricky, and people can have heated arguments in good faith about what belongs in an authoritative/performance friendly version of a work. But its just in the nature of work written for the theater that "authoritative" is open to debate. Especially in opera, of course, we also have a long tradition of performance cuts. The current trend towards performing more rather than less of a score is a good one, but where cuts are kept, they are kept out of expedience or tradition, not some larger agenda, and constitute a relatively minor sin.
3. Productions that use substantial elements of an existing text but are unmistakably a new work: COOL. Here's the category for theatrical "mash-ups" of all sorts (provided ludicrous copyright laws aren't an issue).
4. Productions that substantially change the source material but could easily be mistaken for the original: NOT COOL. And that's what this new Porgy production sounds like. Go ahead and create a new play that is "about" Porgy and Bess. Call it "Porgy 2000". Proviso #3 says that's fine. But the whole enterprise of revival has to do with grappling with a text and trying to offer what is worthwhile about a work to a present-day audience. Without the bright line of the Text, the temptation to serve the lowest common denominator of current tastes to leverage an existing brand is too great, and surely that is a recipe for the most dishonest kind of art.
Others have suggested that what's really going on here is Paulus/Parks' attempting to be diplomatic about while softening "Porgy's" undeniably racist trappings for a modern audience. But why not just have that conversation outright instead of criticizing the quality of the work? If "Porgy" has more merit than other racist works of the period that have been justifiably consigned to the dustbin, that should be apparent in a good production. If it doesn't have merit beyond the catchy songs, then do a production that questions and interrogates that content (or do a highlights CD). What's not OK is sending the original material, with all its complexities, down the memory hole, and assuming that you can pass off something more palatable as the original.