I will prove to you that God exists

[Sheldon]

What odds are you offering he won't come back at all? His posts seemed mainly to be a lame attempt at face saving, so if he hides from the objections, he can pretend his arguments were compelling, and we're just too dumb to get it. I bet he's on some religious board right now, telling anyone who will listen, that he rinsed the atheists here properly. 

We can run a side bet on how many fallacies he repeats.

Different people learn at different rates.  Some take forever.

I still feel sorry for people like that.  They spend a lot of time and effort trying to rationalize ideas which they should simply abandon.

Quite a few years ago, in a discussion, I used an argumentum ad populum fallacy. I was so annoyed at what seemed like handwaving in Latin. That I went way and learned what it meant. The other person was right, I'd made a bare appeal to numbers. I made sure I learned as many common logical fallacies as I could find, and try never to use fallacious arguments now. If I were to do so, I would not only cough to it, I'd be glad, as I'd likely have learned something new and useful. 

As you say, it's hard not to feel sorry when apologists devote so much effort to defending irrational arguments. Sadly, if you start with a belief that you're not prepared to abandon, this is bound to happen. I mean if my position ever required I contradict known fact, or a dictionary definition to defend it, I'd have to discard that belief. There is no belief I wouldn't abandon if the objective evidence made it untenable. 

I have on occasion, in other forums, earned the ire of other atheists, only rarely, when they make sweeping absolute claims, that seem to be unfalsifiable, and I ask them to demonstrate some objective evidence. Recently a poster asserted, without a hint of irony:

"There is no evidence for any god, and there never will be."

The last part in particular caught my eye. So the first depends on what standard one sets for evidence, and whether it is sufficient to base belief on. Generally I always say objective, or objectively verifiable evidence, as subjective and anecdotal claims abound, as do facts that are wedged into fallacious and poorly reasoned arguments. 

The chap was not a happy badger, and I endured as much ad hominem from him, as I ever did from any apologist. He properly lost it, instead of thinking he might have just overreached with this claim. Though it was pretty funny to see someone claim to know what evidence will or will not be forthcoming in the future, then accuse me of hyperbole. he also asserted that atheism was a belief, and would not budge on that, and that agnosticism and atheism were mutually exclusive. A few seconds online could have disavowed him of those notions, but again no amount of quoting the dictionary, made any dent in his confidence. If there is ever a dispute over any word, even if I think I know the definition verbatim, I always check I haven't accidentally stepped on my dick, far better to admit an error than storm off in a flounce, surely?