Saying no new training needed is not something that will provide confidence to flying public.
DO THE TRAINING, even if not needed as you need to give confidence to the flying public otherwise they will not fly. Andy S Grove of Intel had a minor chip problem in 1990's, they saw it as minor and it was. Consumers saw it differently and it cost Intel $475 million and almost the company.
Bottom line it will require Boeing senior bods and airline bods to be on board a few Maxs to build confidence