In a rig pulling two trailers (doubles), which wheels off-track the most during a turn?

AAMVA CDL Manual, Section 6.1.6 "Turn Wide," p. 6-3

With doubles or triples, off-tracking compounds down the line of trailers. A driver who judges turning clearance only by the tractor or the first trailer can still clip a curb, sign, or vehicle with the last trailer's wheels.