Do cables settle in?

IMHO...yes. George Cardas is a big proponent of this and I've actually heard him demonstrate this several times with his cables, (I was a Cardas dealer for many years).

http://www.cardas.com/insights_break_in.php

They settle in about 20-50 hours then they sound better big time!!

Without a doubt .

In my experience, they do settle in, and it applies to interconnects as well as speaker cables.

Yes moving them can affect the sound temporarily. I agree with the Cardas comment. Especially Cardas cables are affected by being moved. The design of Cardas, with all those Teflon tubing in them, makes them particularly prone to having the 'magic' static fields in the insulation collapse if moved.

Now if you have cheap cables, with no Teflon in them, then they will not be as affected by moving them around.
Though I never noticed too much of an issue with Kimber. Still for that last 0.0001% of the sound moving them is bad. Takes a littel while to get it back. Just like turning off equipment. Cold equipment sounds like crap. Takes four hours to really be best.. Some stuff takea all day to shine. Then other folks find it sounds fine after ten minutes. Go figure.