I would file the paperwork, and at least attempt to go through the lemon law process....if nothing else, the combination of putting both of those things into motion should shake things up with ford and make them realize it's time for them to stop jerking you around.....
I wonder if they would let you drive a lot car/loaner of the exact same make/model as yours for a week to note the differences in the two....
I wonder if there's an app for your phone kinda like the sleep-cycle app....the sleep cycle app monitors your movement in your sleep....all you do is set it on your bed.
if you could somehow show that you're required to adjust steering MORE in your car than another identical car on the same commute over a couple of days to show averages....you'd have RAW DATA to prove there's something wrong.
My majorly huge hand-made Focus RS replica build: http://www.focusfanatics.com/forum/showthread.php?t=289061