But the "discussion document", issued by the DVLC in Swansea at the behest of the Treasury, is still insisting that all cars will in future have to be regularly registered and have some sort of licence whether they are off the road or not.
The proposal, similar to one considered a decade ago and dropped in the face of strong objections from owners of cars legally kept off the road for all or part of the year, is being pushed in an attempt to identify persistent offenders who "skip" a month or two before relicensing vehicles in the hope of avoiding detection, as well as those who never pay the tax.
They cost Inland Revenue an estimated £160m a year and it is hoped continuous registration will discourage those who skip short periods, although it is hard to see how it will frighten those who never pay.
The Treasury's proposals will still penalise owners who want to bring their cars back onto the road at short notice, forcing them to relicense their cars for road use at regular intervals only or to pay an extra tax for the right to change their pattern of use.
The discussion document suggests two alternative systems of treatment for cars permanently or temporarily off the road.
The first will allow owners to obtain an off-road licence for six or 12 months, free initially and costing £5 to renew.
The document claims that would mean "no additional costs" for owners who currently license cars for six months of the year, and put them away for the winter.
But anyone wanting to bring a car back on the road before the expiry of the off-road licence would be liable to pay the full back tax, or at least a surcharge of perhaps £15 in addition to the cost of a new current road fund licence.
Even the second option would penalise owners who wanted to relicense a car for road use earlier or later than the expiry of their off-road licence, either to cover for another vehicle that had been damaged or broken down, or to take advantage of unexpected good weather.
A second option would create another special category of temporary off- road licences for vehicles expected to return to the road within six or 12 months.
These would cost perhaps a quarter of the full licence fee, redeemable against the subsequent cost of a full licence.