Copy-editing issues can intrude into even the most intimate decisions. The other day, half-listening, I heard someone who is normally meticulous about grammar say, “They is coming next week.” It didn’t sound like a joke, so I listened more closely and heard him use “they” with a singular verb form a couple more times.
I asked why he was doing this, and he explained that he was referring to an individual who was born male but now realizes that he has both male and female aspects. Nowadays when people adopt a non-traditional gender image, they often specify the pronouns that they want to be applied to them. The person in question, shunning the male/female binary, chose they/their/etc. as the proper pronoun set. But this person is still an individual, so plural verb forms would be inappropriate (though they’d be correct for somebody who feels like two different people in a single body). Thus “they is.”
The print version of National Review used to have an occasional column called “Notes & Asides” in which our founder often tackled fine points of grammar, syntax, nomenclature, and such. One wonders what WFB would have made of all this . . .