It's not that I disagree with most of what you are saying, cos I don't. But the fact is, the Barca game was a one off. An important game. A semi final. I remember the game well. It was a tight and tense affair. I know Barca dominated in terms of possession, even at OT, which made it even more tense. But what did they do with all the possession? Nothing.
Did you watch the FA Cup quarter final last year against Portsmouth? United dominated that game like I have never ever seen anyone dominate a game. They had all the possession, all the attacks and all the shots on goal. But they failed to do anything with it all, and conceded a late penalty (Pompey's only attack of the entire game) and ended up losing 1-0.
IF the United Barca game had been the same and United had been totally outplayed and just hung on for the win, then I would give you that much,. Fact of the matter is, that was simply not the case. It was a close game, as many CL semi finals will be. Decided by the odd goal. Like the Liverpool Chelsea semis of recent years. I am not sure why you would harp on about this one game. United got the goal, were not outplayed, and deserved the win.
You are right that I do not watch La Liga. I do not want to. I have seen the games from there. I do not like the style of football, find it boring, the quality of the teams and players low, and have absolutely no ties to Spain, so I am not sure why I would be watching their national football league. It's not like you watch the Belgian Premier League on a regular basis, or the J-League or any other random league come to think of it.
If you know anything about United, then you will know just ho wmuch Barca are like them - they play attacking, exciting football that fans like to see. Now, if we have to win some games 1-0 along the way to titles and trophies then so be it.