[quote=@Ellri]
Well, if a GM does such, it is a case for the moderators. And restricting access to IC != breaking a group. 
[/quote]

You're ignoring the fact that it gives them the power to. This is the same situation as the thread deletion discussion; if a GM locks everyone out, they've essentially done the same, and that was already solved by restricting that power. I'm all for giving the GM powers to regulate, but highly against giving them the ability to restrict participation after they've already opened the floodgate.