The Crewman's answer
As the title suggests this answer is aimed at purely Cmn(thicko) levels of understanding; before I'm flamed I am a Cmn with plenty of Chinook hours.
Your 'Big Assumption" is correct.
We'll assume that the HP(Handling Pilot) requires the aircraft to spot turn to the left in the 10' hover in these examples(for turns to the right just apply uncommon sense).
To spot turn left the HP applies the correct Yaw Pedal input, as a result this input is fed through the 1st and 2nd stage mixing units and with hydraulic assistance the rotating heads are displaced. The Fwd head simply tilts left laterally and the aft head tilts to the right; as a result, the nose of the aircraft is dragged left and the tail is dragged right simultaneously, thus yawing the aircraft about it's centre.
The advantage of this system is the ease in which the aircraft can be yawed about the nose or tail. This manoeuver often causes issues to inexperienced Pilots on tail rotor aircraft. To yaw about the nose(ie keep the nose above a given point and turn the tail through 360) we simply take the above example and add right cyclic, this tilts the front head right(now level) and adds further right tilt to the aft head causing the yaw to act about the nose. Left cyclic would level the aft head and add more tilt to the front head causing the aircraft to yaw about the tail.
Simple and elegant!!! Standing by for grammar/spelling and tech nibbers.
Rgds iPodder.