EldonC
Most tractors now have 3 positions on the 3 point lift control. In position control the main lever position is directly related to the height of the three-point hitch. In draft control the main lever actually selects the tractive force of tillage implements. In mixed control the function of the main lever is a combination of position and draft controls.
General rule for using the mode selector in the 3 positions is this: Position control is the most widely used and should be used for all implements carried in three-point hitch above ground. In this mode, three-point hitch maintains constant height depending only on the position of the main lever. Draft and mixed control should only be used for tillage. Since pure draft control can be oversensitive, mixed control is usually better. In draft control, the unit adjusts the height of the hitch so the traction force remains constant. The amount of tractive force is adjusted by moving the main lever forward increases the tractive force, or plowing depth.
Hope this is some help on draft control vs. position control. I am sure other people on this board can add more about draft vs. position control.
Cabinholler