It has been my experience that these types of debates are not productive. Atheists and theists simply don’t speak the same language or hold the same things as important. Atheists are only interested in facts. My Jehovah’s Witness friend just cannot comprehend that his Bible quotes only mean something IF he’s right. They will never show that he is. But he keeps throwing them at me and making me look them up because he simply does not comprehend that we are speaking different languages. I say, “Give me a reason to believe there is a God” and he gives me an argument, “Assuming that there is a God and using only my religious text and understanding, here’s why mine is the right one.”
I mean really, what, exactly, did the debate between Nye and Ham accomplish? Did it change minds? Were points made that the opposite side took to heart? Did Ham suddenly become interested in facts and science? Did Nye suddenly decide blind belief was better than facts and science? No. Ham still has a ridiculous creation museum housing plastic dinosaurs with saddles on them which Nye still finds ridiculous.
But maybe you’re thinking smaller. Maybe you’re thinking of debates about particular religious concepts the theist isn’t particularly emotionally invested in, meaning that they are open to alternate points of view. Some level of understanding can be reached there, though it’s ultimately not very meaningful. I have seen on one forum a “one-on-one” debate section, though it didn’t get much attention. Occasionally. Two people would agree to a one-on-one debate and only those two could post in the debate thread. There was a separate thread for comments on the particular debate from everyone else.
The problem was, however, getting someone on the “other side” who was interested in serious intellectual debate. If your belief isn’t factual then it’s emotional. If the reason you hold the belief isn’t because the facts point to the belief being factual then you hold the belief because you are emotionally invested in it. That means you are only capable of delivering an emotional argument, never a factual argument. Counter an emotional argument with facts and you get an emotional response, usually an angry one. Or, even worse, the facts are ignored. I had a friend once going off on “Obamacare”, telling his captive audience the page, paragraph and sentence numbers where the death panels were set up. I pulled up the bill on my phone in its entirety and proceeded to tell him that it wasn’t there. Repeatedly. He kept going. He pretended not to hear me. There was no way facts were getting past his wall of crazy conspiracy nutbaggery (this friend is legitimately nuts, this is not a commentary on all who hold beliefs different than mine). And that happens A LOT with Republicans and theists, whose belief systems and reasons for having them have a lot in common. This friend didn’t want to “debate”, he wanted to “preach”. And that’s the problem with these “debates”. The theist doesn’t come for meaningful conversation. They come to throw shit and screech at the evil people who won’t listen to them.