The Three Skills
Note: the following is based on my own personal experience. Every keeper teaches differently and this reflects the way Ellie, the Israeli keeper, does it. The concepts are the same everywhere.
A keeper must perfect the skills conductivity, control, and change. They were developed at the Alterian Trading Company to make sure keepers anf fortmasters are well equipped to operate the fort and if necessary – to fight.
Force refers to the same concept as in physics.
Formation is the most basic form of training. It consists of a stance that teaches the body the form (hence formation) that allows maximum force to flow through the body with minimal to no damage. Practicing formation involves immediate, excruciating pain. First timers usually fail after one or two seconds. Seven is impressive after a while. Thirty is master-level. This formation is a prerequisite to the conductivity skill.
Advance Formation & Perception
This type of formation is an extension to basic one, but focused on training perception. Perception is the ability to notice force – both external and internal, using the sense of touch, from minute as air movement to actual penetrating hit. Practicing involves the same amount of immediate, excruciating pain. Mastering basic formation does not alleviate it. It is a prerequisite to the control and change skills.
Conductivity is the first skill of the keepers. It involves transferring arbitrarily large amounts of force through the body with little to no harm. It is practiced in the spring room, configured to only have a little portion of the wall visible. The trainee starts with pulling, then turns to pushing, to minimize the danger of the spring wall killing him.
Control is the second skill of the keepers.
Change is the third skill of the keepers. It allows the practitioner to react to perceived changes in force. Change is about the speed of the reaction and fineness of the reaction and not the about the size of the force reacted to. To react to weaker and weaker forces (useful when reacting to an opponent move early on, before it gather power) one must improve perception. It is practiced using a small device that turns a small stone. The training is first to try and put the hand in the stones trajectory without getting hurt, and then advances to try and catch the stone. The device can be set to different speeds. The faster ones will injure the hand if hit. The trick to avoid injury while catching the stone is to continue the trajectory during the catch and slow incrementally.