I'm sure most (if not all) of my readers are familiar with Poe's Law, but for anyone who isn't, a Poe in this context is an atheist who is pretending to be a religious nut. I've been having quite a few discussions with theists lately (mostly on twitter) and have spent my share of time wondering if the people I'm talking with are for real. It does seem like a waste of my time if I'm just arguing with an atheist who is screwing around. So part of me doesn't want to talk to them if they aren't really Christians, but instead are just pretending. If I really get an obvious vibe that someone isn't really a Christian I will sometimes disengage from the conversation.
On the other hand, because of Poe's law it is really hard to tell if those people are actually Christians. And part of me wonders if it is even worth thinking about. The great thing about twitter is that it is a public forum. Even if the person I'm talking with isn't really a Christian, it is possible someone who sees the exchange is a Christian and actually agrees with what the Poe said. It could also be worth it for me to just have a bit of practice arguing a certain point.
I think a much better measure for when to stop arguing with someone is when they get annoying. Whether they are actually Christians or not doesn't really matter much to me, what I care about is that we have a good conversation. If someone is being completely illogical, or if they are jumping from one argument to another every time I make a point, that is when I want to stop talking to them. This is independent of whether they are misrepresenting themselves.