I recently related a similar situation and used the analogy of those little tile games that you slide around to make a picture. First of all - in the words of the great Mr Spock (Nimoy not Benjamin) - it demonstrates evidence of two-dimensional thinking , but that isn't the big point. The constraints of the system require that one change be offset by another otherwise the teacher's workload goes up or the cost go up, or it won't fit into the Sept-June calendar, or something else.

It is my growing belief that you simply can't get there from here. The current system can not change in an evolutionary way because it is governed by this equilibrium constraint.