My question is: Did you consider the possibility that it might be intentional? This is of course not to say that you're required to *like* the choice, but I think that in this case there are good reasons to suspect it that it was a choice (a show of this scale requires the efforts of many professionals to pull off - it's unlikely that they just didn't notice that they were obstructing the audience's view), and to judge it as such, not as faulty execution.
2, just to show that art is in the eye of the beholder, I'll share this reaction from another patron:
"But it’s really all about the second / middle act. I did not want that thing to end. There needs to be a place where that section is performed in a loop 24 hours a day (change the performer / musicians every hour, on the hour) and people can simply come in an watch for whatever amount of time they want, for whatever reason, and leave of their own accord. I’d visit once a week, minimum."
That's all. Thank you for your thoughtful, heartfelt response.