I think the original post was about remarks made at an international atheist convention to inform atheist how to behave (the etiquette) when theists convey some little religious message to them by remarks or deeds. I think it's a bit contradictory to be giving advice about how atheists shouldn't be rude when they respond to being blessed by some idiot's god - at a convention that supports atheism.
These faith bots also believe it's rude for atheist groups to dare to put up a few billboards telling people they exist, yet there should be nothing standing in the way of advertising their savior and informing people they will burn in hell if they don't accept their bullshit.
Richard Dawkins is an evolutionary biologist at Oxford. His 2006 book 'The God Delusion' was on the New York Times bestseller list for almost a full year. He is never "shrill and strident," he doesn't need to be. It's fundies and creationist idiots that are "shrill and strident" because that is all they have going for them. They abhor anyone who writes a book debunking their bad science. They also don't appreciate those who point out that Christianity is a mixture of Pagan and Jewish mythology morphed into the Bible - the Christian religion was synchronized to bring discordant groups together. Nobody expects believers to be convinced by any amount of evidence.
Although, the theists usually know less about their own religion than most atheists do, I don't know of any atheists that go out of their way to lecture theists about religion, and the few who do don't expect to convince them of anything. Atheists usually let theists know that they are not going to be converted. This is what some of these people are calling shrill and strident. It's not, and it isn't rude. Someone waving religious beliefs under one's nose in a public place is rude. There is a place for all of that - it's called your own church where you can express your own personal beliefs with those who appreciate your efforts.
Telling someone (who is obviously proselytizing) "I'm not interested because I don't believe the way you do" is not rude. What is rude is someone interrupting whatever I'm doing by coming to my door or calling me on the phone to bore my ass off with insane delusive fantasies. When someone barges into my life with the threat of torture in order to "save me" I'm going to be the biggest Dick I can be.
I'm sure it's not rude for theists to ask if I have ever read the Bible? However, it would be terribly rude if I asked them if they have read Particle Physicist William J Stenger's book "God: The Failed Hypothesis?" He says, "If we have no evidence or other reason for believing in God, then we can be pretty sure that God does not exist."
Ideas are the mightiest influence on earth.