Hey people, this little trick can be funny to use (to some extent) in either your guilds raid, or even more suiting and enjoyable in a pug which you dont care alot about :P
Here's the deal:
When you queue and enter arena (only skirmish, since you can't queue rated while in a big raid) you gotta make sure you get in as the first person of your team. Doing this will automatically lead to you being the "raid leader" of that arena match.
Those of you who play arena regularly should be aware of that /rw works in there, and since you in this case should be the leader of the game, and also in a big raid, the /rw's you write in arena, will also show up to everyone in your big raid in azeroth, regardless of you being the actual raid leader of the big raid :P
So simply queue to arena. Spam click the enter button to get in before a potential partner
Gain the leader role of the arena game. Do any /rw's you want.
Let's call this an exploit shall we? Okay, yippe!