I agree with the investors being unwilling to go after a money hole. I disagree though that it adds little to the alliance. Perhaps just for my locations (CPH-TXL-WAW, all three *A hubs) removing AB essentially means I no longer fly OW. Perhaps I need it once a year for an odd long haul. And we loose OW connections to many small German airports.
Finally, the amount of BA posters here about earning and burning indicates that BA does not cover a visible part of the market.