It is worth highlighting that fully developed VRS was historically taught because it was much easier to get into in older helicopters than it is now and simulator technology was very basic.
Back when engines weren't very powerful, rotor discs were bigger and downwash speeds were much lower so it was much easier to get to the sort of RoD where you started to catch up with your downwash.
The standard avoidance figures for VRS - keep the RoD below 500 ft/min when speed is less than 30 kts - were probably far more relevant back in the 50s and 60s when helicopter disc loadings were small.
Unfortunately the teachings haven't moved on with the increases in technology, power and performance of modern helicopters.
For most modern helos I think VRS is now best taught in a simulator, but the old criteria (30 kts/500'/min) needs to be updated when programming the sim.
However in a very light helo (R22 and the like) it is still worth demonstrating the incipient stages of VRS and the recovery so that student will learn to recognise and avoid the preconditions for the phenomenon.