You should avoid:

Vague Complaints and Vague Demands

This is where most letter writers get into trouble: they leave unclear exactly what the offense was and why society finds it hurtful. Also, letter writers usually get vague and cagey; they fail to be specific about the behaviors they want changed. (You know it's true. Haven't people done it to you? :^) )

These complaints and demands must be spelled out in patient, logical steps. I can supply these for you. Don't send a letter that merely stuns the recipient but doesn't help him or her to improve.

Vagueness comes from using adjectives (as seasoning) instead of nouns and verbs (as substance). Vagueness also happens when writers write about how the rudeness made them feel but not about what the rudeness was. Vagueness is seen in complaints that use the word "too" -- for example, "You ____ too much," which suggests that there's a line somewhere which the reader shouldn't cross, but doesn't tell the reader where that line is, thus painting the picture grey when it should be black and white. (next...)