Its almost like Concealment was once OP and the development team doesn't want this to ever happen again and has permanently nerfed this build out of fear of failure, occurring a second time that would bring them into disrepute.
It sounds like they have done the analysis and seen the lack of people choosing this class and their efforts have been directed into what's considered as more value added activities or projects. I will bet this issue doesn't even show up on their radar or priority list and they would be happy to let this class die a slow death as indicated by the pervious lack of change in this class.
Yes we pay to play but its not important and its not worth addressing......you will just get smashed in PVP every round (more than normal) and its ok....the odds are you will eventually give up and choose another class. I'm guessing that's what they want you to do. Its been nerfed for so long people don't even bother playing this class in PVP............Mission accomplished:)