One thing about iridescent is the synths and layers plus the lyrics that would turn the whole song more natural... I wonder if the band would release an instrumental of it..
So far the only official instrumentals of a song they've released are New Divide and Numb Encore I believe, but ya it would be great if they release Iridescent Inst.
You can find some LP mulitlayers/instrumentals if you look in the right places. Any LP song from guitar hero/Rock band can be ripped into layers. Unfortunately, Iridescent is one that I haven't seen.