She is actually very clever to say that the DSC isn't an alliance. It's simply a system of communication and as such there isn't a "leading" guild which would by default take command of the alliance.
I don't fully understand how she intends to use it though because all of the guild leaders will be representing their guilds and as such wouldn't see the chat in the DSC. She used an example of being in a guild of 20 members and needing 50 to take down the shatterer (BIG DRAGON), she implies that she would contact the leaders of the other guilds to request assistance.
Great! But is she really going to private message each and every guild leader? What if the guild leader isn't online right now? Is the membership for that entire guild not invited? She is going to private message the guild leaders who are online and are of the biggest guilds (to get the best return) and the small guilds will be left in the wilderness.
She could get the same information by making a list in notepad of the guild leaders and their guild names (well except she wouldn't know if they were online, but as I said a guild leader isn't the only important member of a guild. In fact every single member is just as important).
We need a real alliance system, one which comes with an Alliance chat so that all senior members of every guild can communicate. This is the only way cross-guild communication has any realistic way of working (with any consistency). ArenaNet have confirmed an alliance system will be arriving in the game at some point.
I will echo what she said about guild drama though. Guild Wars 2 is a game where a server is the "team" and there is no reason why one guild should be in direct competition with each other. As long as the server is doing well, and everyone is having fun, that's all that matters.