High rotational spin in the Bulldog was achieved simply by moving the stick forward a couple of inches from the fully back position while in a stable spin. The Firefly is a bit more reluctant - you have to go about half way forward, or centralize, before things get rapid. If a student has not put you into one yet, then you have not flown with enough of them! In my previous job I have to say it was never a problem with NCO students who treated spinning as a 'drill', but Young Rupert was known to extemporize sometimes with exciting results.
Hence - always, lightly, follow through on the controls when Bloggs is spinning. It makes for a slightly quicker 'I have control' & recovery.
Always enjoyed it, but rate of turn can make anyone dizzy!