Just my dumb opinion here, but... there's something extremely implausible on its face about the idea that a sufficiently complex spreadsheet could calculate the difference in value generated from kids going to school versus kids not going to school. If people could be convinced that this was something more than a castle in the sky, maybe it would get more attention. I imagine a bunch of academics put their fingers to…
If the spreadsheet showed education was a net positive, would Caplan accept this and rewrite the book, or would he go looking for more factors and adjustments that could "correct" its result. If he can't accept a spreadsheet showing a positive impact of education, why would the world accept a spreadsheet showing a negative impact of education.
Caplan is definitely the type of person who would either rewrite on not write the book in that case.
But this an implausible question anyway, because it’s not like you get this far into a project without an idea of what the evidence is telling you, waiting to press a button and out if it’s actually Good or Bad.