With the update to the driving test proposing adding motorway instruction then perhaps everyone should be encouraged to have formal instruction? OK....some are not very near a motorway but expecting every driver to be au fait with motorway driving requirements having only been a passenger is not good.
Imposing a 1 hour lesson in most areas of the uk is a one-off cost so not exorbitant, estimating a 2 hour timescale approx. WEst/Northwest Wales are a good few miles from a motorway. Scotland has lon distances too. Perhaps some form of discount based on postcode would help.