Seriously, take a 360 controller, hold left on the d-pad, and at the same time try to rock your thumb toward the up and down directions. It moves a lot! Using one on Windows, you can see in the controller properties how easily it registers diagonal presses. Now do the same thing with a Logitech Cordless Rumblepad 2, which has a very similar d-pad. It's far less finicky than the 360 pad.
So really, how is this new d-pad supposed to fix that?