Zerkers have many problems in endgame PvE, and chasing bosses is only one part of it. The zerker, having no ability to close gaps quickly (and trust me, Dash is useless for this), spends more time than any other class just chasing the boss instead of hitting it. But that's not the only problem.
A big problem is that zerker can never be behind when hitting because no stuns, leashes, rushes, or backstab abilities. This game demands you be behind the boss to do your best DPS and the BT HM robot spins like it's on crack. This is a smaller problem for warrior and slayer who attack much more often than zerker and both have a backstab, a rush, and multiple stuns so they can make it to the boss's backside long enough to land a big skill since they don't have to charge their skills. The robot is the biggest offender at endgame which is why no one wants to take a zerker to BT HM and no zerker wants to go, because you kill the robot from 35% to zero in 2 minutes or the party wipes and the zerker's DPS is just too far behind all the other DPS classes. The zerker is being carried 100% of the time through BT HM and the other DPS need to be overgeared to compensate, because no matter how good you think you are and how incredible your gear is, the mechanics are entirely broken for you.
The other big problem is that zerker only hits once every 3-5 seconds. The zerker depends entirely on crits to do his DPS, more than every other class including archer (the other class which charges all their attacks) which has the lowest base crit rate in the game. However the HM bosses all have ridiculous crit resist, so zerker doesn't crit nearly enough, so in the HMs his effective DPS is cut by a ridiculous amount compared to all other classes including archer which never crit that much to begin with. This means that even HM Kaprima will take much less damage from zerker than other DPS, even though Kaprima can be made to hold still long enough for zerker to hit him from behind, because when it's LOL NO CRIT EVAR meanwhile warrior and slayer are CRIT ALL DAY ERRYDAY the zerker just can't do shit for DPS compared to all the other DPS classes.
To be perfectly honest, simply reducing charge times by 20% won't solve any of these problems. Zerker needs a massive increase to base damage across all skills and a massive increase to base crit rate to keep up with the other DPS if they keep zerker's mechanics the same. I would estimate ~50% increase in base damage and minimum 3x base crit rate is needed just to be on the same level as the other DPS in HMs. Since Tera is dying on the vine anyways due to Bluehole's astonishing incompetence and glacially slow pace of content updates I don't expect anything will ever be done. It's clear that Bluehole doesn't understand anything about balancing an MMO at all from what they've done the last 18 months of live K-Tera, plus their pace of new content releases would make a F2P MMO feel ashamed.
