I would hardly say PI is "counter productive" to the job. As a skill in and of itself, it's actually quite well designed. The problem is that it exists in an environment that can't support it. How often is so much AoE damage coming out that you're going to get it to 3 stacks and then still need it? If the buff lasted a little longer that would help, at least. That issue affects Medica II as well. Not enough damage goes out in general to make full usage of WHM's kit.