Which brings up a good point. Of all the reasons to not communicate with a gent - safety is the best. If a provider doesn't know her client is open to (and enjoys) such unsolicited texting/emailing it's best not to attempt it.
For me such stuff falls into three categories:
1) Immediately after a rendezvous - I think a quick thank you note is always good form. As well as good customer service. But I do understand providers not wanting to send ANY unsolicited responses. Ever. Period. (Ok I probably didn't need to write "period" then use the period punctuation mark which is redundant and more of a spoken inflection, but roll with me here as I'm trying to make a point...)
I had a regular who said "send me a text so I know that you got home safely" after our dates. She was sweet that way. And smart. You see - when I did, she always responded that she had a nice time. It was an open door for a bit of post snu-snu pillowtalk by text. Often times suggesting things we could try during our next date. One of the many reasons she was a favorite of mine. Sweet, smart, and kinky. Check, check, and checkeroo!
2) Responding to posts (or events on the boards) - for gents that have pm capability (I highly recommend it) I think ladies saying "that was interesting" or "that thing you mentioned in your post - tell me more about it." Getting to know someone through pm is a great way to break the ice and is the "safest" of all the methods of communication. So it should be low stress for all those involved.
(On an ironic note - I don't have pm right now, but that will be corrected shortly.)
3) Just randomly checking in. I think this is a wonderful marketing tool for ladies that know how to work it. Some examples of texts/emails I personally like:
"Miss you" - short, sweet. Maybe a bit sappy but so am I.
"I remember you telling me about the thing, I tried the thing, and you were right, it's awesome!" - can be any"thing." These exchanges build intimacy and trust. Also schmoozing a client a bit is never a bad idea. Within reason of course. And some of us guys actually know a thing or two if you give us a chance. Some of us anyway...
"I was out of town and just got back and had a great time. I was just thinking about you" - has a personal touch and also conveys important information (that she is back to her normal business hours and she would like to see you again).
"I had such a nice time with you last time we were together, thank you again" - I don't know of any guy on the planet that would object to such a message. I know this will be a shocker - but us men have egos. And we sometimes like them stroked. Among other things.

This is our fantasy world - remember ladies? So make it a fantasy worth living in.
Use all of the above sparingly ladies and please don't spam us gents. A little interest goes a long way. But I think you will find some good rapport often moves things along in a positive direction. Mutually beneficial if you know what I mean. Wink, wink, nudge, nudge.
I haven't had a long winded post in a quite a long time, boy do I feel better now. And as usual - all of this advice comes at absolutely no cost to you.
And worth every penny.
e