I am currently specced 30/31/0 and I have to admit, it doesnt shine too well. You need at least 20% crit to pull it off successfully. It does make for good grinding though with all the CDs and an awesome stunlock when used with maces. If you are a scrub 70, I would highly suggest putting this off until you havt 20% crit.
I was using 20% as a starting point. 20% is the threshold where you can start thinking about a build such as this. I'm currently playing it with 16.76% crit rate and it serves me well enough. I figure. It might not reach its peak potential until 30% or so, but 20% is a starting point.
I know, I'm trying to work on my gear, but its slow going at 70. By tomorrow I'll have enough honor for the S1 MH mace. Then I gotta work toward every other piece of S1 besides pants. I shoulda stayed ShS at 69 :\