Not important at all. It only affects your saber strikes, Trash and Lacerate.

You do need the cost reduction for Shock. Not so much for Trash. You can drop Trashing Blades if you are still taking it as Trash is out of the rotation.

Dismiss him then Summon him again. Full HP in 1.5sec. In fights, there are medpacks which heals both yourself and your companion.

Don't see how that has got to do with Assassins though..

You are sorely lacking in Defense. Go for Defense.

Surging Charge is only limited to the Deception tree. Both Lightning and Dark Charge are shared between all trees. And no, your alignment does not affect what abilities you obtain.

Do you mean Pureblood specific dialogue options? If you do, then no. There are no species specific dialogue options.

I played Pureblood so I can smack my companions around.

The faster you get Harness Darkness stacks, the more self healing you receive and your Force Lightning does more damage as well. Using Trash to fish for procs is too RNG based while consistently keeping Wither and Shock on cooldown to get Harness Darkness stacks would in longer fights be better. You can read more about our abilities priority on MMO Mechanics. http://mmo-mechanics.com/swtor/forums/Thread-Sith-Assassin-Jedi-Shadow-Tanking-Compendium#Id

No. It is the Sith Inquisitor story. Not the Sith Sorcerer or Sith Assassin story.

It would help if you link your build idea. No one can comment without first taking a look at your build. That being said, the likelihood of it being useful is pretty slim. The trees are now designed in a way that being a hybrid is a pretty poor life choice.

That's not true. With Wither granting Harness Darkness, it is more effective to NOT use Trash to proc Energize. Using Wither and plain casting Shock is now much more efficient.

Only 1 person needs the crystal but everyone needs the MGGS. And yes, you have to be level 50 to use the datacron. You can enlist the help of non-50 players but they won't be able to use it.

Your stats don't really determine what you can tank. It really depends on your group composition and your own skills as well.

That's because you bumped a dead thread that was before there was changes to Raze...

Accuracy affects skills like Trash and Lacerate as well as our basic attacks. Skills like Force Lightning and Shock are not affected by Accuracy.

I would also consider defensive adrenals, medpacks as well as relics as defensive cooldowns.

I would give it a 5. Didn't enjoy the part where you had to go around 'collecting ghosts'.. Seems like a poor attempt to drag out the story.

Stack Defense and Absorb till you get their combined rating of 650 ~ 700 then you can move on to Absorb and Shield rating. http://mmo-mechanics.com/swtor/forums/Thread-Sith-Assassin-Jedi-Shadow-Tanking-Compendium

If the healer is taking damage and the tank doesn't do anything to correct that, the tank is bad. There are plenty of ways to keep mobs off the healers and to be honest, Guard doesn't help when it is on the healer. If CC broke, the tank should immediately taunt to prevent it from being messy. And tank classes have stuns, no harm in using it to gain some time to build aggro on the wayward trash.

The first sentence confirmed that you do not know what you are talking about. The rest of your point is moot. If you don't like it, don't play it.

There are no classes on the Imperial side that uses Cunning pistols so as far as I know, tier gear does not provide for that. There are dailies that give customizable weapons for them though.

Lacerate is good enough as it is for AoE situations as there is no limit to the amount of targets it can hit. As for Dark Ward, it can be a hassle but it is something to get used to.

I don't see why PvE should take a hit just because you 'think' that it is unbalanced in PvP. There are plenty of reasons why you 'fee' that you are overpowered, but instead of calling out for a nerf without thinking about the rest of the community of Darkness Tanks, maybe you should look at what your opponents are doing wrong.

From what I've read, Accuracy is not needed. Most of our attacks are force and won't miss. If you have survivability issues, you could invest in Adrenals, Medpacks and Endurance stims. And of course, doing Flashpoints will gear you up for harder content, especially since Flashpoints do not have lockouts anymore.