As far as I know, the phrase "mit der linken Hand" is not in use exactly in the sense described here. It rather means that somebody achieved a result without devoting a special effort to it. Of course this concurs with "not focusing on what he was doing" but does not mean did not do this deliberately. You may say, e.g. somebody solved the Times Crossword Puzzle "mit der linken Hand".

Quite apart from that, I contend that far too much fuss is being made actually about "intellectual property" and its "theft". I wonder if any author (say, of fiction) has had the sales of his books demonstrably compromised because another one copied some of the stuff! The opposite effect is probably at least as common.
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