I've seen the snow clearing at Oslo. Even in heavy snow, one RW was used for departures and arrivals while the other is cleared with de-icing bays next to the RW holding points. It was impressive. How much would it all cost for LHR to gear up with as many snow ploughs etc as Olso? There would still be diversions with only one RW in use, but how much did LHR lose yesterday, let alone their customers?