BattleshipCannon Vs Demolition

These thoughts are very true. If you use Fist correctly (assuming it attacks every 2 seconds like demo), your DPS shouldn't go too far. For 2 min it will be incredible damage, meaning 400%x8 which equals to 3200%. This happens every 2 seconds. So, in 2 min, you acheive (asuming you don't get hit often) 192,000%, 96,000% a minute.
Fist is 230%x6, meaning 1380%. 1380% damage per hit, 60 hits, in the 2 minute cool-down is 82,800%, or 41,400% a minute. The average % a minute for Buccaneers, therefore, is [96,000%+41,400%]/2, meaning 68,700%.

So, the average percentage a minute is 68,700%. No way close to that of a shadower.

Check facts.
Uncharged Assassinate+DS spam is 600%x3 or 1800% damage, and takes 2 seconds. 30 a minute, so that's 54,000%. Uncharged Assassinate+DS spam.

Add in Boomerang Step and that's 600%x3+1000% = 2800% in 2.7 seconds. Damage/time = 2800%/2.7*60 = 62,222% a minute.

The disadvantage to Shadowers at bosses comes from the fact that there aren't any supports that help them much. SE has a minimal effect on those high damage %'s. Time Leap only gets you a few more seconds of Smokescreen. And they don't have any self damage enhancers such as Combo, Venom, Expertise, and so forth.