[defrost]

Heh.

Wikipedia reinforces my understanding .. it's been in common use for centuries and only relatively recently have a few dipshits declared it to be "wrong"

     Singular they has been criticised since the mid-18th century by prescriptive commentators who consider it an error.

Who d'fuck gives a toss about prescriptive gammons tellin udders de write ways to use da Engrish, 'hey?

FWiW the Oxford English Dictionary is descriptive and not prescriptive.

All Hail the OED.