We have too much of this saccharin sweet but vacuous tech support. What you really need to do is. 1) Be polite even when they are not. (The authors approach of doing this makes you sound like a teenager trying to take the car on a date, skip it) 2) hear what the customer is really saying not what you think they are saying. Don't immediately bucket them. 3) Calm the customer down. "Yes Ma'am, I don't know why it isn't…
I have learned that this is a really nuanced skill and requires a level of maturity that is beyond some people.