The secret inner mysticism shit is definitely bullshit, but some (most?) internal/soft martial arts do contain stuff like what we're talking about. For example, Tai Chi does contain a variety of nerve/joint manipulation moves - the problem is all the flowery shit they build around the explanation of why it works: when really it's just that they're striking someone in a nerve cluster.
The strikes themselves often actually work, but not because you're drawing out their chi energy or something - it's because you pulled out all their chi energy by punching them in the throat.