"You don't need to know the phrase "ad hominem" to know that it isn't fair to attack the person rather than debate the ideas/opinions in an argument,"

...indeed! But if you DO know the phrase and others like it, and what they mean, you 'may' be able to not only detect bad arguments by others, but to adjust yourarguments so that they are not unfair and obviously slanted.

There are two issues working: one is how to define and identify bad and unfair arguments and work out reasonable ways to discuss issues; the other is the problem mentioned above about people who simply NEED to be right and couldn't care less whether they are fair or not...or need to cause dissention.