I didn't get hit on the head with a big rock, but reading this post was the next best thing. I think it was the line where he said "So the whole debate about the marriage penalty is complete nonsense. It’s a debate over a non-issue; the pretense that there is a financial penalty to getting married is simply wrong".
Then I got this great idea for raising money for the govt. After all, you know they need and deserve the money, and they'll do something really intelligent with it.
So I thought, who is it who has the extra money to be taxed? After all, that's the idea behind progressive taxation, isn't it? - that we can decide that some people ought to have to pay more in taxes than others even though they don't get any more out of the govt for their money?
Ah, a brainstorm -people with roommates! They're saving money on rent, utilities and other things, right? Why shouldn't the feds get a cut of their savings? Sheesh, you'd think those silly taxpayers thought it was their money when they can see it says "United States of America" right on it.
Here's how it works - all we have to do is make everybody report to the feds and their employers every time they move in with someone else, platonic or not. Compliance would be handled with the fairness and efficiency of the IRS. Failure to comply would incur the same penalties that falsification of income taxes would. There would be regular audits where everyone would be forced to produce utility bills and deeds or leases in their own name. Throw in random bedchecks too - tax them extra if they're sharing a bed and thereby saving even more money. And if they're having sex, count the avoided expense of prostitution as taxable income.
What's this? You think it's none of the feds' business whether you room with someone else or not? Actually, neither is your income, but you have to file income tax forms all the same, so what does privacy have to do with anything? Let the feds count the avoided costs as ordinary taxable income - in the words of the post cited, "if you support a graduated tax schedule, you should support this outcome as well."
I guess that was sarcastic enough to last me a few days. Really, what justification is there for considering the incomes of both married partners in their taxation that doesn't also apply to other cohabitants?