Originally Posted by
bicycle
From the logs linked above, it's clear that you just don't know how to play AS on multi-target fights, and you do massively better on fights you go COP for (Thogar, Gruul, H&F rankings are way above your single digit performances on the others). So the expansion dropped, you learned COP, and now that AS is good with BRF fights and BRF gear, you fell off a cliff.
Time to learn AS, then. Your basic priority is to mind blast on cooldown, keep shadow word pain up on all possible targets, and spend your shadow orbs with plagues before you cap out and start wasting them is nearly mandatory to show you how many orbs you have incoming from AS). Anything else (VT, Mind Flay/Insanity, Surge of Darkness proc mind spikes, whatever) are secondary concerns. Get a unit health bar addon that will show your dots on the floating name plates, and just keep scanning for your dot durations.