Opher, I think I may actually be in danger of disagreeing with you on gestalt being too big a word as I find it quite a decent possibility. Mainly because within that gestalt you could also include the perceptions and personal beliefs of the person "extending ki" which would neatly side-step the spiritual/non-spritual arguments as the intensity of the belief would be one of the main weighting factors for it's successful application, whether that belief came from an innate belief in some sort of spiritual energy or adequately described body mechanics.
So Damian, my components off the top of my head would be:
(belief + confidence + relaxation)* situation
Jim, mea culpa, I have been guilty of this and you're right to remonstrate.