I have, untill recently - been running all out darkness, as I was under the assumption that this may be the best way to solo, however what you said regarding 23/1/7 woke my interest, even though I play mainly PVE. However stupid my question may be I hope you will find the time to give it a quick and short answer.
Q.: could you please give me a fast breakdown on priorities for what stats go for. You do write about it, but my head was spinning in the end, and I truly don't get it.
This spec can be a fun spec to play even for pve. But if you are not going to pvp with it, I just wanted to warn you that all three other trees are far more effective for pve. All you are basically doing is Thrash/Shock spam until you get an Exploit Weakness proc then you Maul and of course Assassinate below 30%, and DF as needed. As far as stats, your standard 25% unbuffed crit, 75% Surge and the rest go to Stamina and Power. The true power of this spec is the CC, You get Force Pull, out of stealth Spike and an instant Whirlwind. Which is why it is the strongest spec for new 50's because you don't have the gear for the huge damage numbers the other specs can do. If you are Darkness spec because you enjoy tanking then I would recommend going all the way up the Darkness tree, it is far stronger for tanking. If you are using this spec for dps, then I would strongly recommend going Deception or Madness.