Maybe I missed it, but nowhere do I see a recommendation to ditch the term 'set' in relation to flap setting and instead require both crew members to respond with the actual number. Perhaps their SOP picks this up somewhere else?
IMHO the word 'set' should be banned from terminology for critical items. It is only OK for variables of a minor nature such as lights and certain automated systems that can't readily be mis-handled.
I bet there is not a pilot out there who has not at least once selected the wrong flap for take off; hopefully with the error detected by the other crew member.