Has Davidson's law broken down

Sid Davidson, longtime Accounting Prof and Dean of the University of Chicago Business school proposed a 'law' that the paid price of a B school education (or indeed any education promising higher earnings) should on average equal the first year compensation derived from said schooling.  Here's a datapoint from an instapundit reader:

While visiting with old college friends on New Years’ Eve we did a back of the envelope calculation on the cost and value of our BA degrees in Accounting from 1981. We attended a small well regarded Midwestern liberal arts college from 1977 to 1981. Tuition, room and board was between $3,000 and $4000 per year so around $16000 for our BA. As entry level accountants in public CPA firms we earned a salary of around $17,000 per year. So we earned in salary an amount equal to the cost of a BA degree in our first year of employment. Now that same college, which my youngest daughter is looking at attending costs $42,000 per year. If she earned her BA in Accounting it would cost her $168,000. Her possible first year salary as a CPA? Not even close to $168,000. Maybe around $45,000. What a change in 30 years in the value of that BA in Accounting.

This example would suggest that the value proposition has gone to hell.  However there are a couple of caveats:  First, list price is not paid price, I'm sure the average student pays far less than list.  Second, in most industries real prices go down over time as market contention drives innovation to reduce prices or at least to improve quality.  We know that real learning quality hasn't changed so why aren't the prices lower, much lower than they were 40 years ago?

Our educational establishment has suffered from incredibly wasteful and destructive state funding and manipulation that have done nothing but drive up costs and retard true market driven innovation.  We need to bust it up, bust it all up.