Feels like you have not even read anything I actually wrote, your just looking at the spec and not understanding. If you really do have questions then actually read my post, then actually try the spec. It is quite obvious you have done neither.
As far as the Hollow talent that gives you a 10% heal, that is a nice talent and if you want to tweak the 23 points a bit to get you the talent it wont hurt much. As for me personally I use Overcharge Saber right off the get go, when I am 100% health and when I have roughly 60% damage mitigation through Dark Charge and Darkswell. So the heal isn't needed. I found when I ran a full Darkness build that I ended up saving Overcharge Saber as a defensive cooldown instead of an offensive one. As of right now my first 12 sec is 100% offense.
I run a 23 point darkness build currently. I told you I ran a very similar spec as you run, with some changes to better align my darkness tree with improved overcharge saber, for instance. I ran it without chain shock to take insulation. In fact I would tell you if your running deception with insulation you should take fade, but you don't like anyone making suggestions to you.
You have a full darkenss build options currently:
Darkness with heavy maul and chain shock (23/11/7)
Darkness with heavy maul and insulation
Darkness with death field and whirlwind and light maul. (23/1/17)
Darkness with Wither, chain shock (31/0/10)
Darkness with Wither, chain shock and heavy maul (31/3/7)
Darkness with Death Field, heavy maul and chain shock (23/5/15)
Darkness with Force Lightning, light maul, chain shock, Death Field (27/1/13)
All of these play slightly differently and I have played all of them. What I don't appreciate from you is this sense that dark maul was somehow your build that no one else plays or understands. There are many assassins who have had maul in builds as openers or finishers. Prior to its current revamp I found after much fighting that 31/0/10 pvp was the best build for the roll I played in warzones.
Maul is unpredictable. Unlike smash, or snipe or other big hitting skills it requires more timing to hit. To take insulation as your build has requires dropping a host very powerful attacks.
For instance, I enjoy using maul, but a lot of times having no instant cast attack I can use at 30m now is a big issue in your build. Especially with well structured groups or on fleeing targets. I find my build shares that issue. Having dealth field for instance helps to give us greater range and FL on x3 is very powerful with recklessness.
Wither is very useful to healers who get slowed/rooted. When you can slow down the attackers pursuing your guarded target and reducing the damage output you've taken stress off the healer.
I have played plenty in darkness. All I was looking to do is try some hybrid build specs. Maybe next time instead of saying you didn't try my build "Waaaa!", you could tell us or post to us stats, strengths, additional info, whatever to supplement your posts.
Instead of just falsely proclaiming we've never tried your build. I have tried a bunch. It makes pugging more fun. So please post your builds others. I am always looking for something fun to play.