His point is lost on both of you.
Its not necessary to get nailed, as 2015 illustrated, but it provides more margin for error in the event that the balance of the hemispheric regime is less than stellar....as this season illustrates. We wouldn't have to worry about the timing of all of these SW's, which has been awful. The mother load of arctic air would not have been allowed evacuate in advance of the ongoing soaker. In 2015, the ridge out west was positioned perfectly for several weeks, this season it is less stout and displaced west....so we cut.
This season would be perceived entirely different right now had we an NAO...today is a perfect example. This season is a good counter to the "we don't need an NAO" rebellion.