The big problem with retrospective action is that Sky seem to be deciding which deeds are to be retrospectively acted upon.
We had similar in the last Chelsea game with the issue of the yellow card. How many times have they glossed over dives and fouls when it suited them? Remember them trying to get Tevez to bring the game into disrepute after he was much more clearly, unfairly booked for diving v Norwich, in 2012?
As somebody said earlier, if Sterling's team-mate, Balotelli had gotten away with the same action, he'd be vilified by Sky. Nobody is under any illusions either, surely, that Sterling's being as close as England have to a rising star was a major factor in both the officials and, subsequently the media, ignoring the misdemeanour.
I could bleat on but I suppose I'm only preaching to the converted. Sterling has a case to answer. The fact that he's not answering is an indictment of the FA and the fact that it has been glossed over is an indictment of the media, particularly the station that covered the game live.