This will exploit your Arena & Rated Battleground Match Making Rating. MMR or Match Making Rating is the “hidden” rating which you can only see at the end of a Rated Battleground or Arena fight.
What you do is get one of your Highest MMR players to relog using the "Log Out" button before gates opens (After gates open works too). What happens is, You will get double his MMR.
It will tell you in the chat that "xxxx has left the battle" as soon as he logs on, When he joins the battle again, your MMR will be boosted by the difference of MMR this player does.
Example, 10/10 players is in the RBG
player X Relogs(Leave the battle) - Keeps the MMR
Player X Has come online(Join the battle) - MMR will Raise by the difference he makes.(20 or something).
To exploit this in a bigger scale, Get ALL of your highest MMR players to relog and your MMR will raise by 100-200 Match Making Rating.
It might even work to relog several times to boost the MMR by even more!
Doing this you will always be over your standard MMR, and ALWAYS get more points than you should
Doing this in the opening of an Arena will cause you to gain extra rating.