Many people using tgethr or breeze don't know how to setup a listserv. I've got my in laws on tgethr. They don't understand how to even attach files to their emails. Google groups doesn't highlight code fragments I send to other developers. There's all sorts of things like that where 37signals and I are trying to copy these old ideas and make them our own.
It's on my priority list actually for some future projects to make it super easy to quit and migrate data out of my stuff to a competitor.
Are there any examples of this leading to success?
Sometimes it's a great hook to help potential customers feel more comfortable doing business by giving them a good reason to trust you. You're doing what's right for them as a customer, not necessarily what's right for you as a business.
Why not write about that, then?
I think you have a good point, but it seems poorly made. You lead with a question whose answer is an obvious, "No, because the idea predates both of us by decades." It just ends up not being relevant to the subsequent discussion.
Like I said, the real problem is that you start off with a question which has an obvious answer, but then ignore than obvious answer, which makes it look like you either somehow don't know, or are trying to ignore it. It just seems like a bad way to start off a discussion of how ideas propagate.