Nick – I think ‘total joke’ is a bit harsh. Its still one of the best in shorthaul business class. What BMI is doing – picking off a couple of mid-haul routes and running long haul business class – is a great idea, and shows there is a need for more space for longer flights.
But the fact that, in your example, BMI are selling at 1/2 price shows there must be other things people value. I’d worry about pricing if BA followed suit – they carry much more business class pax on these routes, and in a CW configuration, there wouldn’t be much left over for cheap seats.