I would identify a representative set of specific circumstances which would benefit from 'vocal training techniques', then go into detailed explanation of the physiological changes that effect a benefit in each specific circumstance. Now that the generally applicable part has been covered, you can detail various techniques designed to achieve the effects. As each person will have differing degrees of success with different exercises, list many, but at the outset state the ultimate goal for the technique the set of exercises are designed to develop, exempli gratia "You will feel X once it has worked" (I don't know if this is possible).

If you are clear that one is only learning how to use their body more effectively, I should not think considerations of identity will prove problematic - if it does, abandoning the exercises undoes the effects, correct? I would also mention that incorrect use of one's voice over long periods of time damages it; increasing one's ability to use it correctly will help preserve their ability to produce voice into the future.