What would the utility of the Andragogy in Practice from a practitioner perspective be?
Andragogy is the study of teaching methodology for teaching adults. The practice of andragogy instructs on several points of adult learning that is different from childhood learning. The utility to practitioners is taht more effective learning can occur.
One of these points of difference is that adults have a background of experience they bring with them to educational environments while children and adolescents have limited background they bring to educational environments. You might say they acquire their initial backgrounds through their educations.