"MLH is someone who drives below the speed limit in the middle lane isnt it?"
Sigma has put it perfectly, joko. You need to read some of the earlier answers (and more importantly the Highway Code, particularly para 264) to understand. Neither your speed nor the prevailing traffic conditions (i.e. "there was nobody else about so I was not causing any inconvenience") are relevant. You should drive in the nearside lane whenever possible.
Of course there will be occasions where "whenever possible" is debatable and that's why the offence (careless driving) is subjective. However there are many occasions where "whenever possible" is not arguable and that's the instances these new measures are designed to deal with. Anybody wishing to argue that it was not practically possible for them to return to the nearside lane has simply to refuse the offer of a fixed penalty and instead opt for a court appearance when they can plead Not Guilty.
As has been mentioned, before passing a driving test drivers have no experience of motorway driving and many have little idea of the rules and the law pertaining to them (though similar rules apply to multi-lane dual carriageways which are not classified as motorways). Perhaps a second test needs to be taken to assess a driver's competence to drive on motorways.