BigEndBob: That's ATC who are required to have 'average' anemometer displays as standard with 'instant' available on request. AFIS units are not required to have 'average' anemometers (although the CAA recommends it) hence they MUST broadcast the word 'instant' if transmitting instant wind.
Whopity: It does have relevance in the AFIS environment if a pilot (instructor or not) uses it in a busy circuit session.