[TomSwirly]

The Chicago Manual of Style IIRC has this, also perhaps Strunk and White, and apparently the NY Times in 2010:

https://afterdeadline.blogs.nytimes.com/2010/04/13/faqs-on-s...

[leephillips]

Hmm. Either the Time’s guide is inconsistent or they changed their rules between 2010 and 2015.

You’re correct about Chicago (you do RC); at least my 1969 copy.

My 1959 Strunk and White doesn’t seem to have anything about this, but it also doesn’t have an index, so maybe it’s in there somewhere.