Opening as a Dark Knight?

[SpookyGhost]

nope

you will be able to land 2fc plus butcher combo.

again you probably mistaken this opener with 7 gcds one, this one require Infuriate>wait30 sec raw or veng then pull around 10sec or so.

There's some disadvantages to the 3x FC MT opener. Mainly that you'll need to delay Berserk by 4-5 GCDs meaning that, like aleph_null said, your TA window will be full of non-Berserk'd GCDs. On top of that by delaying Berserk you're also losing potential aggro generation, which could come back to haunt your DRK later. An even more important point, though, is that you're completely wasting RI or Vengeance as a defensive CD by popping it pre-pull. You're also delaying RI/Vengeance until after both FCs, this is especially harmful for Vengeance as now you're in a situation where you either need to have the WAR as MT for an even longer period of time (cutting into Reprisal and LB proc chance) or you have to swap and waste a bunch of Berserk'd Vengeance reflects.

Personally I'm a fan of this opener:

[Unchained] -> Tomahawk/Overpower -> [Foresight + Awareness] -> HS -> [Brutal Swing + Bloodbath] -> Maim -> [IR + RI] -> Eye -> [Berserk + Vengeance] -> HS -> SS -> [Equilibrium] -> BB -> [Deliverance] -> HS -> FC -> [Infuriate] -> FC -> Maim -> Eye -> Fracture -> [Pacify]

e: Should also mention that this is assuming we're using Unchained, if we forego Unchained then your TA alignment is better (since you're doing the standard 50s OT opener as MT) but you're also losing a ton of aggro (which means more PS), Defiance's HP buffer, and Equilibrium's heal.