The BoxFlow is a design that has been used by various equipment
for years.  The center "road" gets wider and narrower, so you can
see the past history of the enhance band.  You want it wide, to meet
the threshold.  The outer boxes are the "inhibits" and you want them
small.  If they get large, they encroach on the inner box, which inhibits
feedback.  They are inhibited when they go outside their boxes.

So the clinician and trainee watch the roadway going by, looking
for wide parts, as being the goal.  Keep the outer boxes small,
by reducing movement and muscle artifact.

This visual coaching adds to the value of the feedback.