Best (or at least pretty good) practices

[First in a series of "Rewriting the rules of journalism" posts, in which we will make bold assertions that our way is better, and then come back later on and retract them after running up against reality.]

Assertion:
When you're doing an interview, or otherwise requesting or providing information, the best medium for doing it, hands down, is text. This is for three reasons:

1. Those of us whose mouths are not firmly attached to our brains will be able to say what we mean to say, rather than whatever happened to escape this time;

2. We have some time for reflection, to decide exactly what it is that we mean to say;

3. The end product is a perfect record of the entirety of the communication.
By this I mean two things: I have a perfect record, since I can review it; and anyone else also has a perfect record, since they see exactly what was communicated. In contrast, face-to-face or phone conversations involve sending and receiving visual and auditory signals galore, any of which can completely change the meaning of the communication in a way that doesn't come across even if we were to type it out verbatim.

So, if I want you, the reader of my weblog, to know exactly what I think I know and how I know it (so you can judge for yourself), I should publish the email exchanges.

But there's an immediate, strong "invasion of privacy!" feel to doing anything of the sort; and if the other person didn't plan for the exchange to be public, it's just plain unfair.

My general rule of thumb on publishing emails - an unwritten rule until now, just based on what seems fair - seems to be this:
If it's out of the bounds of civilized discourse, and one of the parties has given permission, it can get printed. If it's so far inside the bounds as to be innocuous, ... not sure. I think I ask, just as I do if it's somewhere in between.

But what about a case (hypothetical, so far) where the emails are necessary to tell the whole story, but permission is not granted? I guess we'll cross that bridge when and if we come to it.
But first we'll try to find another route.[edited]