Oh, I see what you meant. Ok, I get it now. You are still wrong but at least now we are on the same page.
Ok, let me explain what I meant. The side frame that goes around the ipad (not the back plate) is 0.5mm taller. (that what I meant by thickness). And, as a result, the metal will have better structural rigidity than before. It won't be much as the thickness of the ipad (the tallness of the side frame) is only 8% more so its not going to be crazy different but it will provide a little improvement.
Same goes the other way, if the ipad was 1mm thick it would be easier to bend than if it was 10mm thick. Its just physics.
Of course, thats only assuming that all other parameters remind the same or don't have affect on it.
So yeah, the new iPad will be better if we take this into consideration.
And I take little better than nothing so to me this is a nice change.