It's a more interesting piece than it sounds like from that summary, as he tries to wrestle with some of the complications of the idea.
And then the problem of who exactly is eligible must be addressed. Would a biracial voter qualify? A black immigrant? And what exactly is an election official to do when Rachel Dolezal shows up to claim her five-thirds vote? The government shouldn’t be the sole arbiter of who gets to be black — nor flirt with archaic prescriptions such as the one-drop rule in determining a voter’s race. The most straightforward approach would be to limit access to weighted voting to those American-born citizens who have demonstrated through government documents, such as drivers’ licenses or birth certificates, that they identify, and are identified by others, as black or African American. There are bound to be instances where this approach is challenged, and one answer would be to model guidelines after the general requirements for establishing American Indian or Alaska Native ancestry as outlined by the Bureau of Indian Affairs, which involve establishing that a lineal ancestor belongs to a specific tribe and then producing vital records that document a relationship to that ancestor.The 3/5ths compromise didn't give blacks 3/5ths of a vote, though: it gave states representation in the House of Representation based on counting slaves as 3/5ths of a person. (I suppose we all understand that the South wanted to count slaves as whole people, and the North wanted not to count them at all.) If you wanted to do this in a way that mirrors what was done during the slaveholding era, to count blacks as 7/5ths of a person (a more obvious standard than 5/3rds, being 2/5ths off in either case), it would be purely to determine how many representatives in Congress each states get.
Now, that would doubtless increase black representation in Congress somewhat. It wouldn't have the wild swings that are posited in the article, though, because it wouldn't affect the Senate or the Presidential election at all. It would only mean that places like Georgia would have more congressional districts, and because black voters were considered 7/5ths of a person, more of those districts would end up being gerrymandered into black-majority districts than currently is the case.
The author points out that 90% of white Americans are opposed to the idea of reparations. I am not among them: it satisfies my Viking sense of justice, because it is a parallel to the weregeld. That was also inheritable by the family (indeed, it was often paid in cases where the person wrongly offended had been killed). We used to help the tribes in Iraq negotiate diyya payments to settle similar feuds. Assuming we can work out a deal of that kind, I would not be opposed to making the deal. The terms are, though, that the payment resolves the debt in full -- honor is satisfied, and we discuss it no more.
For that reason, the proposed 24-year period of weighting doesn't strike me as the right approach. The payment should be a one-time thing, something everyone agrees to accept as a settlement of the debt, so that we can finally put it behind us forever.