In the short time I've been here on MT, I've seen a dozen or so guys come on here telling everyone else that they don't know what they're talking about, "so here's the real deal."
I try not to engage it, but please understand: there are plenty of people here who grew up in the ghetto, live in high crime areas, and have also done what they've needed to survive. Plenty of people come here thinking they're the only one. That's not going to stop, but I really wish it would.
I don't know where you're from. But I grew up in the projects myself and having lived in many other impoverished areas, I know first hand that trash talking has always been a fact of life in places where fights occur. And for the same reasons I stated in my previous comments.
And when it comes to real fights, you said that trash talking is a way for someone to convince themselves of the courage they don't really have. And you know what? Sometimes that's true. And you know something else? There is absolutely nothing wrong with that.
When I was young, I've used my trash talking abilities to get dudes who wanted to fight me (and who I thought would have beaten me) to back off. And if that didn't work (I'd say it was 50/50), it helped me muster that courage to go through with it. It's a concept called "think, do, become" or "acting as if." And it's never a bad thing.