The ONLY way a captain could do more DPS is if they removed all the captains buffs.

Look at how we increase the damage of the group/raid while red traited.

10% from mark
30% from banner
25/15% from to arms
35% from oathbreakers
8% from bladebrother
2% from herald
3838 tactical/physical mastery and 1151 critical rating from sure strike
Our banner also increases crit to the whole group
15% attack speed routing cry
Blade of Elendil damage

Lets also look at the other buffs we provide during a fight while red trait.

7/4% damage reduction from to arms
15/9% outgoing healing
5% outgoing healing from sure strike

Now other utility while red trait
Rallying Cry Heal
Inspire Heal/Power
Muster Courage

For those arguing you need more damage do the math. Take a boss fight and lets calculate how much damage you added to the group/raid and now add it to your own DPS. I bet you beat everyone by a long shot.