It isn't contrarian - shell doesn't stretch. I have spoken to Paul G at AE, the Horweens and Kathy at Alden and they all say shell will likely, because of how it lasts, fit looser. I think in your case the calf is probably expanding more to meet your foot. At the end of the day, all that matters is that they fit.
based on my experience, I totally agree that shell does not stretch