We ALL knew the Bedroom Tax would create a greater cost for the taxpayer – at least, those of us with any forewarning knew that this would be the case.
The Conservative-led government (including the Tory Democrats who prop it up) was told that the cost would be greater and ignored the warning.
My impression was that they wanted it to cost more, as part of their overarching “starve the beast” policy to make public services unsustainable.