I believe that it is the insurance market that one day ( should it feel compelled to do so) will drive the market back to more "experienced" co-pilots.
Why? How many accidents have been attributed to low experienced FO's? I read a lot of AAIB incident reports and I have to say I don't recall seeing many incidents caused by low experienced FO's. I'm sure there are a few, however there are also many reports where very experienced flight crew have made mistakes.
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