Well, wise @$$ as it may sound...
um... tell them to 'Read the Book'?
As far as a rational for it, there really isn't one, it is just yet one more thing that putting hard numbers to can lead to some interesting paradoxes. That said, it is in the rules and if they really want to grumble, remind them that they have options for improving their AC that lie fully withing the RAW.
um... tell them to 'Read the Book'?
As far as a rational for it, there really isn't one, it is just yet one more thing that putting hard numbers to can lead to some interesting paradoxes. That said, it is in the rules and if they really want to grumble, remind them that they have options for improving their AC that lie fully withing the RAW.