Richard Whittall with a great review of the weekend and more, for The Score’s Counter Attack blog:
Is this simply a weakening of the traditional big clubs? Or are smaller sides using a different approach? It depends on the club. City have proven vulnerable both on the break and in set-pieces, while United seem more unable to score in open play and put results out of reach. Other sides have not been afraid to match opponents in shooting, though as Sunderland demonstrated this can lead to a lack of fitness as the game wears on.
Could also be simply the big times taking some time with new managers and new players. Moyes, Mourinho, Pellegrini, new players at Tottenham, and Clark being an excellent manager at West Brom. The simplest explanation is often the correct one.