Well it's all in the phrasing, isn't it?

The majority of bmi flights have business class. It's a majority of Heathrow routes that are single-class (although that will also end when the last of the useless once-a-day services to Alicante, Venice, Naples etc get axed).

The Scottish and Irish business routes are not an exception to a rule but the bread and butter of the LHR operation, accounting for most of the slots and the revenue. That is why BA would love to get its hands on bmi, as PUCCI suggests. The number of slots that could be freed up by removing duplication is considerable.

And yes, the bmi website (and its entire e-commerce operation) is an unmitigated disaster and a total disgrace. Thankfully, bmi hasn't outsourced all its ground staff (unlike some carriers I could mention) so all my ticketing problems are sorted out by knowledgeable staff at my local airport.