I'm afraid it's not so straight forward. For those who've been following her developments on and off court, what RedShuttle surmised aren't entirely "some retarded reasons". She is not only involved in political activities and duties, " the recent shuffling of pairings" that CBA is actively experimenting needs time for the players to adjust and adapt. As normally happens in life and work, any introduction of changes, esp if they are sudden and sweeping,requires an accommodation period to work things out and overcome teething problems before they begin to bear the hoped-for results (assuming the right decisions were made in the first place).
Yes, in that AE final, the INA pair did play very well, no doubt about and clearly deserved to retain the title. As for Zhao Yunlei, I can do no better than to quote Redshuttle's words:"Hope that she can sort out her issues and get back on track". One doesn't become an Olympic double doubles gold medallist in XD and WD without having any special abilities, if I may put it that way.
As kwun rightly observed, Team CHN sems to be about 10% off their peak form post-Olympics. IMHO, as far as human affairs are concerned,nothing progresses (or regresses) in a straight line, i.e. linearly, whether up or down or level, but zig-zags along the way.