Response is better than non-response

Plainspeak is better than jargon

Folksy is better than formal

Formal is better than sloppy

There should be one -- and preferably only one -- obvious reason you can't
respond to that email when you see it

Though you needn't _check_ your email all the time

Say what you mean, even (and especially) at the expense of awkwardness

If you don't know the answer to a question, acknowledge receipt
and forecast an answer by a specific date + time

Concise is better than verbose

Verbose is better than inaccurate

But inaccurate isn't the same as inexhaustive

If you're acting timely, honestly, and in good faith, you can't go wrong

When appreciating another person's time, showing is better than telling

But you should definitely tell too

Line breaks are one honking great idea -- let's do more of those