For FRA and MUC also Lufthansa have special price from 88 euro return all inn and a lot of daily flights to choice.
Not a bad deal considering the free food, drinks and baggage etc. but businessmen are not too bothered about that on a LON-FRA flight of approx. 1h to 1h 15m unless they are the people who refuse to travel in business as it is 'common' and only first will do or they are loyal LH (there are a number of them!) with large amounts of miles on their cards.
However, for the realists - U2 would give LH a good go on a number of routes - remember BA at LGW?