Ki energy described as the flow of water through a fire hose, preventing it from bending, is common sense.
Our bodies are over 80% water.
I might buy your proposition IF your skin was firehose and you could take that 80% water in your body and physically direct it with your mind to create 100's of psi of water pressure...but you can't. If ki is "real" then how can I take anyone and have them do the same technique using their extensor muscles and no ki since they don't know what it is. Fairy dust not included.