I can't get anywhere near 3k dps
I spent some time at the target dummy last night and I couldn't get anywhere near 3k dps.
standard flametoung and totems, no heroism
I tried these both with manually applied flame shocks
/castrandom lvb,lb
/castsequence lvb,lb,lb,lb,lb
and compared them auto applied flame shocks and chain lightnings
/castrandom lvb,lb,cl,fs
They all had similar DPS against a single boss target dummy. the first two were almost impossible to run out of mana as compared to the last one ( 76% mana compared to an 0% mana using CL )
the best I did for DPS was apx 1900, the leatherworking with the wrist buff got closer to 2000 dps.
Xenoca
Xenocad
I then ran an instance and found that using the first castrandom cost me a lot of DPS against trash mobs, i was only getting some 1300dps instead of 1600+ dps I used to get.
I can see that the mana efficient cast sequence is probably manditory against raid bosses like patchwerk however I just can't understand how you got the extra dps.