Yes, I must say I notice this too, and several users over at PianoWorld have also commented on it.  One of them suggested that the likely cause is the very different sampling techniques used, with the CFX sampled using the built-in facility, while the Steinway was sampled using the robot.

Regardless, it is slightly curious that it was not normalised in some way prior to release.  It suggests that VSL regard the velocity curves/midi sensitivity of the two as broadly equivalent, but it's hard to see how.  The Steinway sounds almost brutally harsh on a linear velocity curve and zero midi sensitivity.

But don't make it so huge, like the controller curves in the SYPlayer. Otherwise people could accidentally read values or set proper x-over points... ;)