I agree strongly on his thesis, that being polite is a good thing to be and that too many folks are oblivious to its usefulness. I'm not so keen on his writing

I agree strongly on his thesis, that being polite is a good thing to be and that too many folks are oblivious to its usefulness. I'm not so keen on his writing style, but he makes a number of good points. "Useless in high school but extremely useful later on": yes, school is when you'd expect to learn such skills, but high-school is such a toxic environment that too many folks learn the opposite of politeness (like how to dominate in an interaction, or flee it). "it provides insulation against bad situations" (the gloves/dirty laundry paragraph): very much so. Politeness and etiquette provides guidelines to interact in situations that would instinctively lead to aggression. "it lets you gather information about people": I don't like the manipulation undertones of this part, but it's true that with a little skill you can turn many a conversation into a mine of information and bonding. "touching and personal space": as others have mentioned, this is very flexible across cultures, but I believe that everyone has some level of personal space boundaries. Break these and the other person becomes defensive, uncomfortable.