The reason I'd say "Don't DPS in Dark Charge in Group PvE" is because Dark Charge grants additional aggro. Which means you risk pulling the mob off the actual tank. Many of the darkness talents and skills also grant additional aggro. Of course, when you're in Dark Charge, you're a tank yourself... So pulling aggro isn't as huge a concern as it would be for other DPS classes. I think that's the crux of trying to use the Darkness tree as a DPS tree, in order to get the best DPS out of it you're essentially also being the best tank you can be (just have to have Dark Ward ready to fire if you pull aggro..?) That fight you described I'm not familiar with... is there a tank on the mob at all? Or is it just you? If its just you, Dark Charge obviously makes the most sense, if its all DPS people and no tanks, also Dark Charge, if there's a tank on it, is he out-aggroing you everytime? Are your healers aware you may pull aggro and are ready to keep you up if so? And of course I'd question/be very skeptical of any claim that Darkness as DPS out damages a full Deception or Madness spec. But if you're a tank most of the time and occasionally DPSing, eh, whatever.

I use a computer, personally.

Are you using Dark Ward whenever it's up? You're using a shield and not a focus in your offhand, right? We really need that running to get to the mitigation levels of other tanks. I'm low 30s as well and haven't felt squishy really, I tank far better than Khem, and use Andronokis as my partner mostly for the added killing power. You'll get Harnessed Darkness soon which is more self healing/damage, so that'll help too.

Lightning is your only choice. If you're in Dark Charge, you'll be pulling aggro from the tank and making the whole group angry. Of course, you'd also be a tank, so... Too many of the Darkness talents require you to be in Dark Charge or grant extra aggro. You don't take too big a hit to damage for being so, but in a group situation, it isn't ideal. For Solo PvE, Darkness "DPS" you'd still run in Dark Charge, as no one would be hindered by it. PvP, run in Dark Charge. Group PvE Darkness "DPS", you're going to have significantly reduced DPS compared to other specs, and you either run in Dark Charge and make your group angry, or Lightning Charge, and get not so much out of Darkness tree.

Here's another thread where someone asked the same question: http://www.swtor.com/community/showthread.php?t=279461 You'll find a lot of good math at the end. The conclusion: You could do DPS as darkness, however, you'll never been anywhere near as good as if you specced Maddness or Deception instead.

Yes. Without Surging Charge active you only get the +Crit % to maul, not the proc.

This is the best looking robe I've seen in game. The one I saw was a green item though... anyone ever seen an orange version of it?

One problem I noticed right away: TORHead Skill Calculator hasn't been updated, but the Induction skill now requires you take Surging Charge to unlock it. So, you'll need to move things around a bit (drop one from Darkness to get Surging?) or drop Induction entirely.

Are we talking pushback, the making you lose 1 tick of the channel, or Knockback, which Harnessed Darkness does nothing for? I ask because there is often confusion here, people thinking immune to pushback means they shouldn't get knocked away, when it just means we should not lose some of the channel time when getting hit. (Apologies if you were correctly using the pushback term, but its a common mistake, and I don't have HD yet to have tested if the pushback works correctly myself)

I played a Feral druid in WoW, and I'm playing a Darkness assassin now. I preface that to say I know what you're thinking with Feral, but I haven't played the DPS assassin trees to say for certain. Its similar, the energy mechanic you will feel at home with. If you go down Maddness, you pick up some DoTs, but also more ranged ability and targeted AEs, which is different. Deception will focus on Maul more, which is a bit like Shred, but doesn't strike me as being as spamable to Shred was. I find my assassin as darkness to be more fluid and flexible than a Feral was, we have some ranged ability, some AE, position and stealth aren't as vital, our DoTs in Maddness are ranged and have a cast time or work off procs. I don't think there's a perfect WoW-analog here, except maybe a DeathRogueFeralPalaWarKnight.

I'm not sure that is the common assumption. The various skills that have an impact on Discharge say Discharge, not Charge. Cracking Charge in Madness for Example: "Increases the damage dealt by Lightning Charge's Discharge." Or Crackling Blasts: "Increases the critical strike damage dealt by your Discharge effects and Shock by XX%" So, seeing those, with Electric Execution saying just Charge, the safer assumption is its only going to up your Charge proc damage. I really see Electric Execution as a skill less for Darkness spec people to take, and more for Deception to dip into after filling out their tree. 9% to Surging Charge + all the Deception talents to charge proc damage is more interesting. But for Darkness Dark Charge, its as underwhelming as you're thinking.

Saber Marshall's robe looks pretty close to that, the orange you get from the Revanite quest line on Dromund, not exactly, but very much a simple black robe with a hood. I haven't yet found much that goes well with it though.

What level are you and what is your lightsaber called? When you first start, you don't have a lightsaber, you have either a Vibrosword or a Training Saber, which is a metal object/baton type thing. Towards the end of the starting planet you get a real lightsaber.

pushback and knockback are not the same things. The game really needs to add these terms to a tutorial or something.

Yes. 45% of the time it will do the extra damage, no extra button press required from you.