Diaspora/Diaspora

In which context would I see this message? Would it be directed directly to the user?

It's unlikely seen by a regular user.

As you may know you can connect a pod with a Twitter to allow cross posting functionality for your users. To do that you have to create a so called "App" on Twitter, this app has some settings, one is whether it can write to Twitter at all or just read. The default is read only, as Diaspora needs to write we're now checking the apps configuration. However the best place we can do that currently is when a user tries to connect to Twitter. We then abort the attempt and display this message. So it's likely that the only person ever seeing this is the pod administrator trying out the Twitter connection he just setup.