Let's put it this way: I've spent plenty of time looking at the OEM STI map for the VA chassis.
As you can see, there are only three throttle mapping modes. These maps are not interpolated. I've noticed switching between I and S that the mind does adapt quite fast to the quicker throttle mapping. Going back to I from S makes the car feel dead below 3k RPM, but after a little while driving I get used to it again. I really do think it's in your mind, but if you are very concerned take it to the dealership.