Well maybe, but the point was that the system of play was effective on the day, and you don't change it if it's working.
If we replace Watkins for Ings etc, etc, that doesn't really have much influence on defending set pieces. That's purely down to organisation. I pointed out in the match thread that Buendia should not be marking Van Dijk on set plays, but to change that you don't need to change the way we play.
Also we need a new striker in the window, but again if the way we play creates chances for them, we don't need major upheavals.