So, I got an idea. What if the energy that is used in psi is not actually a misty vapor that runs out if you use it too much, but the mind focusing on a task and trying to complete it through non physical means. Here is an example.
You want someone to feel a warming sensation in their hand. Normally, we 'create' a ball of energy, program it to be hot, and send it to there hand. What if we are not actually sending a ball? What if instead, your mind is remembering what the feeling of warmth is like, and transmitting the feeling to the other person. When we take in a feeling, chemical signals are sent to the brain, and can be stored as a memory. When we try to recreate the feeling, our brain calls upon the memory and duplicates the chemical signal. The objects in motion create waves that can be interpreted as the feeling 'heat' by the focused target when talking about a new practitioner, and virtually anyone by the seasoned practitioner.
This is just a theory. Any feed back would be great.