Don't get me wrong, I love arguing and rhetorics, but there are people who abandoned all sense of truth and rationality in debate. Rhetorics are a weapon, and like every weapon it should be wielded by people who know that with great power comes great responsibility. Sure, one can argue about objective truth and whether it actually exists, but many who wield rhetorics don't give a damn about any truth, be it objective or subjective — they care about winning. And they don't care about the price everybody has to pay for that win.
Despite that I still think putting yourself in a different position to defend is a good lesson, but the goal of rhetorical training shouldn't be to form ruthless mercenaries, but thinkers who can wield the word and still admit they are wrong in an actual, real world debate, when they are shown to be so.
If you are one of those people (like me) who likes debate for debates sake, you have to be especially careful. Like people who like to use guns we have to be especially aware when we use it and for what reason.
Most people who use their rhetoric have never been given the moral compass to wield it.