The critical engine of any multi-engine aeroplane is of academic interest only. Something useless to file away for the anal check pilot given to asking petty questions.
When an engine quits, you don't have the luxury of selecting which one to shut down, or for that matter the luxury of treating the less critical one (if it has been considerate enough to be the one which has failed) as less serious than its cohort with regards to correct handling technique.
Back to the original question, I go with the idea that originally they needed a larger housing on one throttle lever to accommodate the Go-Around switchology, probably ordered 10,000 of them and now need to use them up.