Yet another of your baseless assertions...you offer no evidence that this is true in the real world. As has been pointed out to you many times before, the angular difference between "centered" and "near the shoulder" is minuscule at the distances and speeds we're talking about.
Evidence:
http://www.cyclistview.com/laneposition.htm
Or, they could have simply ridden in the normal way, and used their mirrors to notice that the truck was not moving over. In that scenario, they can: a) move left a bit to try and force the driver over, and/or b) bail out if they think the driver isn't going to move.
Why would they expect something to be wrong if the truck did not move over if they are riding to the right of the fog line. I can't remember if you claim to use a mirror or not, but you write as if you're ignorant of what anyone who regularly uses a mirror to monitor to the rear would know: when riding to the right of a stripe, the vast majority of motorists make no adjustments in speed or position prior to passing the cyclist (see the above clip for a brief demonstration of this even without a stripe).