GMs decision to keep Opel reflects optimism about the car industry and concern over a lousy dealTHE decision by General Motors to abandon its sale of a controlling stake in Opel to a consortium led by Magna, an Austrian-Canadian partsmaker, has embarrassed and angered the German government and alarmed workers. After months of negotiations, and with an agreement about to be signed, GM made a last-minute handbrake turn, unexpectedly announcing on Tuesday November 3rd that it will now hang on to al