nubfury

Hello, I have some noob questions regarding raiding as a Fury and would like to ask for you help. I read on the old Nostforums that executing with a lot of rage (for example after consuming a Mighty Rage Potions) is a waste of rage and that you should use bloodthirst and whirlwind first. Why exactly is that? And is it true for every gear or only if you reach a certain gear threshold? Thanks four your help in advance.