What you typed was this –
“But slipping in a last minute replacement? That happens on Broadway literally every night of the week. It's what understudies do. It's literally their entire job. I'm not sure why you think doing that would have been ridiculous.”
That’s incorrect. It doesn’t happen on Broadway literally every night – I gave 2 recent examples to prove my point that you dismissed. Understudies don’t go on literally every night – they only go on after they are ready to go on – not before.