You want no accuracy rating at all.
The only attacks that benefit at all from are saber strike, trash and assassinate. They are not used often enough to make it worth having any accuracy.
All your force abilities will hit 100% of the time anyway and most part of your damage and even greater portion of your threat comes from those.
Missing a few saber strikes is never going to make noticeable difference.
Even if you did want more damage or threat, many other stats would benefit more.
You want all tank stats and no accuracy rating at all.
I would suggest you read here why having no accuracy is bad http://www.noxxic.com/swtor/pve/sith...ty-and-details
tanks wonder why they have to guard dps instead of healers since dps keeps pulling agro
Bosses have a 10% defense chance which can be offset by 10% Bonus Accuracy for a total of 100%
As a tank you hit harder with 110% accuracy. That means me the dps wont pull off of you as a tank.
Btw this was tested in my guild by are tanks the boss has a 10% bonus to defense which is negated by 110% accuracy. Are guild tanks spent less time taunting off dps when the followed noxxic.com guide.