Correct me if I'm wrong but doesn't the problem lie in the new orchestration and not adaptation? It's easy to confuse the two.
My understanding is that P&B features new orchestrations unlike any before. That, in itself isn't the problem, it's that the spirit of the piece has been lost and replaced with a less effective one. A lot of you are talking adaptation, which involves taking an orchestration written with a certain number of musicians, instruments, and notes in mind, and adapting it so that it can be performed by a group of either more or less musicians. Most people don't have a problem with adaptation because 9 out of 10 times it closely follows the original orchestration, upholding its integrity. A whole new orchestration discards any semblance of the original and replaces it with something else.
I think what makes this difficult is that, like the issues with Les Mis that I can't seem to shut up about, the new P&B orchestration isn't inherently "bad." It is a valid interpretation and one that effectively steers the piece toward a satisfying direction for most, especially those who are unfamiliar with the original piece.
But to someone who knows the original work well and who have been moved by its musical message and what it tells/offers/infuses the piece with, having that replaced with not only a slimmer number of musicians, but a whole new musical identity that pales next to its intended one AND is touted as an "improvement" over THAT OTHER version, well, it's infuriating.
It's important to understand both sides so that we don't have one side thinking the other are stuffy purists who don't know how to let go, and the other assuming those who love the new version are a bunch of musically illiterate morons with bad musical taste. This clashing is a sad event to witness because both sides are wrong about each other, but absolutely correct and valid in how the newest incarnation personally affects them.
In the end, Ms. Paulus' strategy of undermining the original while elevating her own is at fault and makes people resistant to her vision, when a little bit of respect and mindfulness in considering those who love the original piece would have prevented alienating them.
It doesn't mean everyone would have loved and accepted her alternate take, but it wouldn't be the highly emotional reaction the show is getting. And I'm only strictly talking musically. We all know the production has other problems but I think this is the most important.
It's bad enough that something precious has been lost, throwing in this snotty attitude that it was lost for the better is what burns.
Recreation of original John Cameron orchestration to "On My Own" by yours truly. Click player below to hear.