A lot of these guys honestly limit/squash the hell out of their channels and even clip the master at some stage. What you should be looking at is a wall of sound style of mixing and arrangement.
Most of that stuff, while it may seem busy with all the change ups and such only has a few elements going on at a specific time and usually none of it is overlapping each out frequency content wise.
It allows for a lot louder of a mix, and even then like I said some of these guys will continue to squash the individual channels, the busses, or even the master.
Take a look at pop music over the ages, even commercial metal, and that should steer you more in the right direction for that style of sound.
http://www.gearslutz.com/board/high-end ... ffect.html
Hell one of my faves, Current Value has a very clinical usage of frequencies within arrangement, compression, etc.