Comment 78 for bug 194472

The security team's perspective has been addressed sufficiently by Jamie, I think.

One of the difficulties here is that there is no distinct line between what is a "server" and what is a "desktop"; tasks from each are often commingled on the same machine. Anyone who has spent any time in the #ubuntu-server IRC channel has seen how common it is for people. Commonly, web application/service developers will develop and test using a web server on their desktop and then deploy to a production server environment. As such, they are likely to get confusing behavior, and despite what we might desire, these people can often be quite new and inexperienced in using Linux environments; precisely the people we're trying to help. Anyone who has spent any time in the #ubuntu-server IRC channel has seen how common it is for people with less experience asking whether it's okay to install desktop software in a server environment.

I personally like Thierry's proposed approach of using a pop-up dialog when DISPLAY is set, though there may be some issue I'm overlooking. One tricky bit is that for where ssh X forwarding is used, the server is unlikely to have gksudo or other X based dialog utility installed.