Matt, you are simply off-track... you are trying to tag a new definition on to an already established term. Scientist lives in a world where every term needs to have one reference to reality, and one distinct reference only. If reflex describes more than one phenomenon, than it is useless as a description, and requires more words to allow a hearer to understand a speaker's meaning. This distinction of terms makes for more accurate communication.
So, Scientist said:
The problem that I have with this is that reflexes are clearly defined phenomena.
and,
The thing about a reflex arc is that it is set. It cannot be modified or changed. It also is characterized by the stimulus always producing the exact same response. When a physician taps your patellar tendon and your quadriceps contracts, this is simply because the tapping stretched the tendon, which stretched the muscle. The circuit for the stretch reflex is wired so that when the muscle stretches (like it does when you being to lose balance and fall), the response is to contract (so you stand back up).
When he might have said something like:
A reflex arc is a neural pathway that controls an action reflex. In higher animals, most sensory neurons do not pass directly into the brain, but synapse in the spinal cord. This characteristic allows reflex actions to occur relatively quickly by activating spinal motor neurons without the delay of routing signals through the brain, although the brain will receive sensory input while the reflex action occurs.
So, a reflex occurs without brain interference.
Now, we are using the term, "reflexive tension" to describe the phenomenon of how muscles fire in sequence to stabilize the structure. This phenomenon includes the actions of both reflexes, as defined, and brain interaction (whether unconscious or conscious). So, "reflexive" is not an accurate descriptive term as it includes brain action. Reflex can't mean both, "without brain" and,"with brain" at the same time.
This is all that is being said... we agree that the phenomenon does exist, that it is trainable, and that it seems to improve the quality and authenticity of movement when appropriately challenged (like Brett and Grey pioneered), leading to injury prevention, yada yada yada...
So, if you're emotionally attached to the "thing", fine... but try to pause, and hear what is being asked. Alistair quoted Grey who is asking the same kind of questions about strength and stability: how do we define these "things". No one has yet to attend to the actual question asked (I guess Zach did, just up top here).
This is a great discussion, and a worthy pursuit. I come into the same problem as Scientist when I try to describe this very real phenomenon. Intelligent students familiar with physiology question my description, with disbelief.