Manchester United’s fans may be frustrated, but the extraordinary high expectations at the club and the air of [relative] decline that surrounds Old Trafford is also partly a symptom of a corporate culture that has built up over the past 30 years. While anonymous, shadowy figures hurl abuse at Ed Woodward, the Glazers and possibly the media, United’s unhappy fanatics have to realise that success should be cyclical and the club’s success in the 1990s and 2000s was built on the advantages United accumulated from becoming Britain’s first capitalist club. United floated on the stock market in grand style (I remember the prospectus) and this set them apart from their peer group. But at the same time, being a public company meant they were…