Aah... a clear line of demarcation.
Matthew's proposition - There are no things in the martial arts that cannot be explained by physics.
Mark's proposition - It is a fact that some things in the martial arts cannot be explained by physics.
It's at this point that the experimental physicist would devise an experiment to test which of the above propositions is supported by experimental data. Anyone care to contribute to the design of said experiment? Thought experiments welcomed.
This is tricky. What exactly comprises a physical explanation? For example: I believe that in principle, the workings of the human mind can be explained by physics (I think in principle the mind is a huge number of fairly simple interconnected processing units exchanging and processing signals), but does that mean that all psychological phenomena can be explained by physics?
Body mechanics is probably simpler than the workings of the mind, but it is still a complex subject, that also involves the mind.