I accidentally posted what was supposed to have been today’s post — an item about transit agencies buying overly expensive stations — on Sunday morning. Meanwhile, all day Sunday I was driving with my family from DC to Brooklin, Maine. So today’s item will be a bit quick.

What I wanted to do was follow up a bit on last week’s article, “Give the vaccine to the elderly” because it played out in an odd way over the weekend.

The sequence of events is, roughly:

• Last week, the CDC’s Advisory Committee on Immunization Practices (ACIP) came out with interim guidance about the Covid vaccine. This guidance argued that frontline health care workers should get vaccinated first, then after that essential workers.

• A number of people, myself included, argued that this recommendation was a mistake and that ACIP’s own modeling suggested that prioritizing the elderly would be better. ACIP’s slides seemed to suggest that they’d recommended prioritizing essential workers on the basis of a not-very-cogent …