Hypothesis: Martial arts stances and kata are not for fighting but a strength and conditioning program for fighting

Tradition is what we do because we are not comfortable with seeking evidence disagreeing with the way things have always been. It's not always a bad thing, the tradition of turkey on Thanksgiving works out pretty well for everyone except the turkey. When they get opposable thumbs I'll start worrying about it.
According to legend and somewhat supported by historical fact Bodhidharma was a Bhuddist monk who travelled from India to China via multiple other Asian countries and transmitted Zen to China. When he arrived he found the monks to be so out of shape that he provided them with instruction on how to hone their bodies called yi jin jing (muscle and tendon changing).

Apparently monks were regularly robbed and this instruction helped to decrease such activity. Perhaps Bodhidharma was preceding Gable with "Conditioning is the greatest submission hold". If you watch the video you will see a Shaolin monk go through exercises that are less combatative and more conditioning. Now if we expand the supposition that many martial arts have prearranged exercises that are at best suboptimal and look at their movements not as fighting but conditioning, it may explain why people trained in more traditional styles practice forms one way but fight another. Why do positions in yoga look so much like stances?
Since you had to do something while standing in awkward positions, why not codify some of the arts techniques into this training. I've heard multiple explanations for the low front, horse, crane, and cat stances, none of which have ever rung true. For example, "We train the low front stance so that when you are in a fight your natural tendency to rise up will give you a functional fighting stance". Or "Because Okinawa is a coral island, they could not move or fall because they would be slashed to ribbons by the coral, hence a low solid stances". This might further explain why kata is generally taught to people below shodan "first grade" or blackbelt. The first few years weren't teaching you to fight so much as conditioning for fight training in the future.