While this does seem obnoxious to me, I must admit that carry on bag size rules are..... grossly abused by MANY passengers across most US carriers.
I believe my carry on bag fit the old guidelines; whether it fits the new ones or not, I'm not anticipating any change in behavior on my part.
And I'm certainly not about to go out and spend another arm and leg on a carry on bag that's ONE inch or two smaller in a certain dimension.
