After a long story that ended with my deciding not to buy 3K steering rack/torque sensor set, I just pulled the relay for the PS and decided to drive a stiff car for a while. Its going great. So great that I swear that the car is turning more easily. I really doubt that my shoulders have become THAT much stronger in the last few months. I don't think that it is just my getting used to it. Is there a reason for this? The steering still feels tight, with no play in it, but is there a chance that something important is working it's way looser without the electrical assist?
I'd say that there is a greater likelihood that you are getting used to driving a manual-assist car; and a much smaller likelihood that something is coming loose. However if the latter concerns you then you should have the steering gear inspected.
I expect with skinny, low rolling resistance high pressure tyres that the steering load wouldn't be that great in the first place