I am not completely sure what the best method of implementation would be for this, maybe simply adding it as a option on the specific weapon skills. It occurred to me recently that certain skills, such as Cluster Bomb on the Thief bow should really be able to tap this skill. By this I mean, when a skill has bleed stacks, at 10 stacks it should give a stack of Torment. I feel this makes sense, as 10 stacks of bleed are a lot to amass, and would in my mind cause additional stress and damage.
Just my thoughts, any other opinions?