a) It’s the author’s view; but there could be many similar depending on operational safety culture, an operator’s balance of safety vs economics, and the ‘value’ placed on safety re corporate image.
b) Not necessarily so. National law is currently the highest level. The use of best practice as a measure might help level the playing field for ‘just culture’ and to close the gap between the legal and aviation views of error.
Anyway the question was if best practice will work – irrespective of the benefits of bettering minimum standards of ‘compliance’ or the slow progress of legal change.