“ If you get banned you are banned from those stated on your license.”
That is only partly correct, ummm. If you are disqualified you are banned from driving ALL mechanically propelled vehicles whether of a class covered by your licence or not. There is no connection between disqualification and a driving licence other than the fact that any licence that you hold is automatically revoked if you are banned for more than 56 days and a new one has to be applied for. If you are banned for 56 days or less your licence is returned to you after it has been endorsed by the DVLA and you do not need a new one. As I said in the earlier question, if you manage to obtain a licence you still may not drive if you have been disqualified.
The grass cutting scenario is interesting and there are two aspects to consider: (1) the status of the machine and (2) the status of the place where it is being used.
Firstly the machine. Pedestrian controlled powered mowers are specifically exempt from licence and insurance requirements and they do not fall under the definition of a “mechanically propelled vehicle”. Thus a banned driver would still be allowed to use one. Assuming that the mower on the golf course was a “ride-on” or tractor pulled example these would certainly fall under the definition. A “mowing machine” (other than pedestrian controlled, as above) requires a class k licence and a tractor requires a class f licence. So a banned driver would not be able to operate one of those on a road or other public place.
Now the place. Places other than public roads are covered my most aspects of the various Road Traffic Acts. These are known as “other public places”. There is no definition in law of these, but plenty of case law exists to define them. In general they are places to which the public has “unfettered access” during opening hours. So Tesco’s car park would be a “public place” but an office car park open only to employees where the public was prohibited entry either by a barrier or signage would not. A golf course (whether privately owned or owned by a local council) would probably (though not certainly) fall outside the definition. It would depend on a number of factors including the circumstances in which it is run, how people gain admittance and whether the public – other than people who had made a booking to play golf - has unfettered access. In short, it would be for a court to decide whether it falls within the definition or not if a motoring offence was laid on the green keeper. My own view is that a council run golf course would probably insist on its employees being licenced and insured to operate the mower and so a banned driver could not undertake the task.
As an aside the EU is considering legislation that would make it compulsory for all ride-on type mowers to carry third party insurance even if they are being used on private land.