Well actually, I'd put myself into the first group of pilots. I certainly do not remember observing or being pointed out at anything unusual when on 737. I would hazard a guess based on what you had written but I see you prefer not to describe more until somebody else comes up with an observation similar to yours. It was your reference to AB (you discussed with AB friends and they say there's no such behaviour, correct?) that had me thinking what is the difference between the two. Freeplay and tensile behaviour of control cables was the first idea and second being that THS could flex with elevator movement with a 'control reversion' effect that may or may not be recognisable. Although this would apply for AB as well.
Sincerely,
FD (the un-real)