He's not saying that the spreadsheet is an integral part of the homework process at his home (I think). Instead, he made an experiment (limited in time) to see how much homework his kid has. Then took the results to the school's principal, hopefully ending the experiment.
> [snip]
> The problem is institutional, massively reinforced by the parents.
> [snip]
> It is complete craziness and I hate it and I feel terrible for my kid
I sincerely can't understand what it is I'm reading.