Well first off, while it isn't theoretically impossible that United might get relegated, it doesn't seem that it is likely to happen, just as it isn't likely that teams like Arsenal, Liverpool or Chelsea might get relegated. I guess this is mainly because of the wide gap between the standard of the teams in the Premier League.
Secondly, as a United fan, while I would never want the team to be relegated, in the highly unlikely event that it DOES happen, it MAY not exactly be a terrible thing. Why? Read on...
As Mr Orange has astutely pointed out, there are hordes of people who support only the top teams because they keep winning. Now that is so wrong. I've always been of the opinion that once you support a club, you should do it for life, and don't support them just cos they're winning. Like orange, who has been a faithful City fan for 17 years (even though we all know who's the pride of Manchester

), I myself have supported United for 11 years.
If United do get relegated, then all the glory hunters and armchair supporters will just leave for good and then we'll finally know who the true United fans are.
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Virginity is a state of mind