I've just realised that I can't debate theists

[Tempus]

Of course if you were able to debate with grace and without resorting to anger or insults, like 'religiards', then you would win the debate by example, rather than words. Whenever I find myself responding in anger, its because I'm focused on proving how right I am, rather than a sincere desire to understand the other person or persuade them for their benefit.

I agree. Anger is often a natural response to challenges to one's own position as well as to propositions that one considers ridiculous. Feeling anger sometimes can't be helped, but to let that anger inform responses in a debate is a sign of poor debating skills in my opinion. Anger fuelled responses in a debate are superfluous at best. In my eyes there's no excuse for unnecessary insults on online forums. Posts can be reviewed and edited. In fact, I came close to making unnecessary slights in the writing of this very post. I just read it over and edited it out because it helps no one.

As for the saying "you can't reason a person out of a position they didn't reason themselves into" - this can't be true. Many atheists are former Christians, Muslims, deists etc. If Christianity (for example) is unreasonable, as many atheists hold it is, then how are Christians reasoned out of it? Reasoning skills are learned over time. Sometimes people are lucky and have a good school or good parents which send their minds in this direction from the get-go. Sometimes people stumble upon it by accident from a position of ignorance, like I did. Expecting to reason people out of their positions in one sitting is a tall order. People take time to process information, particularly when there's an emotional investment. Further, sometimes it is even necessary to teach the very reasoning skills that underpin one's argument before the conclusion is accepted.

I see people become frustrated about people not accepting the evidence of evolution (again, an example) - but perhaps their frustration would turn to understanding if they realised that their opponent places different values on evidence. Perhaps in some cases the problem would be revealed to be that person A is amounting a large pile of evidence, not realising that person B doesn't actually value evidence (or physical evidence). If person A is to establish their case they must first show Person B why evidence (or physical evidence) should be valued, what types are valid and why, which evidence is better than which and why, etc. However, it's often that Person A in this scenario will simply give up and say that Person B is 'wilfully ignorant' or 'stupid' which may not be so - it may be that their differences in values must be resolved before a fruitful discussion on evolution can ensue. A video by Evid3nc3 on youtube about Evidentialism comes to mind.

This is a good video which is somewhat relevant and contains suggestions about managing oneself in a debate: