"and may be harmful to our performers.
That wording makes the actors sound like performing dogs. "Distracting" would be better."
When I saw MARY POPPINS, I was seated dead center first mezz, third row back.
SPOILER:
When Mary Poppins takes her final flight exit, she flies TWO FEET in front of the first mezz. This guy in the audience, four rows back who is DIRECTLY facing her on the house right side, stands up from his seat and snapped a picture. His camera had the most annoying flash I had ever seen.
Ashley Brown, for the rest of her flight up, was obviously disorientated. She kept blinking her eyes and you could tell she was uncomfortable.
This is extremely dangerous for her, because she has to climb down stairs to get back to stage level for her curtain call.
I think 'harmful' is a good word to use.
"The Spectacle has, indeed, an emotional attraction of its own, but, of all the parts, it is the least artistic, and connected least with the art of poetry. For the power of Tragedy, we may be sure, is felt even apart from representation and actors. Besides, the production of spectacular effects depends more on the art of the stage machinist than on that of the poet."
--Aristotle