I think Harvey is a treasure to the Broadway community. I agree with his views completely. In some cases people have paid $100.00 to see these stars, and when they're out (No matter HOW GOOD the understudy is) it's bound to upset some people. If you're really sick or there is a family emergency that's fine, but the performers should be there otherwise.
If Lincoln were alive today, do you think he'd be pleased with his tunnel?