(aside from playing the wrong advanced spec.)
This video shows two (I assume) relatively well geared players. One is powertech, one is mercenary, both are Pyro spec.
According to Bioware, we're all within 5% of each other, right?
According to some people on the forums, a Merc Pyro should never get beat by a PT Pyro.... because cleanse trumps all, and it's 'easier to kite' with.
So here's the video in question. Disclaimer, this is not my video, but I came across it looking for my daily youtube PVP dose. I apologize if the owner of the video did not want it posted.... and maybe if either person from this video peruse the forum you could add insight.
So all things being equal, BW's statement on DPS, their expertise at class balance, etc, etc.... what is the Mercenary doing wrong to get beat so soundly?