I'm pretty sure my logic is flawed somewhere and this is just to get the constructive criticism and have someone answer this question.
I have a simple question, I feel like I'm lacking knowledge in this small area of a Rogue.
I see plenty of Rogues that are high rated and even mediocre one's putting a weapon chain to reduce disarms. Guilty as charged I would do this too without really understanding the "why" do it behind it. It never made sense to me why this would go on your offhand weapon when a warriors disarm takes out your mainhand, a shadowpriest disarm takes off your mainhand, and a Rogue will make you drop both BUT key abilities for rogues require a mainhand not an offhand. I'm talking about kidney shot, rupture, etc.
I just see it like it should be on a mainhand to really get any benefit, what's the use of shortening your your offhand's disarm time if you don't use it for much. (that's an understatement, I understand your OH pulls damage as well, but special abilities wise. I can only think of Shiv at the moment)