Even if the squads are weaker there is no quarantee to win the games, because it is a cup competition. Other big teams have failed as well to win Europa league. Look at the latest world cup big big teams have failed to beat the smaller ones, because the small team players will play the games of their life to achieve success, same with europa league. Nobody would have thought that after LVG left the following manager, next season would win 2 trophies and get CLQ(not via league but luckly via europa). It was a good achievement to lift the club tad higher. Then the second season came in and he got the best finish in the league post fergie wich was not 3th but 2th. Almost won a trophie again as well(Fa cup). People say that it was to far away from city, but 2th is 2th at least better then spurs, arsenal, chelsea, pool. Also players might have been demoralized seeing that there is no way to catch city at all. The only downside of his first two years is not beating Sevilla, but he would have lost in the quarters anyway to a much better squad. He managed to make United strong again at home, unbeateble, great european defence record, despite having average players in defence.
What could he have dome more with our average defence, shambless fullbacks, sanchez not being messi'like, lukaku mediocre as well, no proper right winger, etc. To many problems in the squad and no investment. What ole done is nothing sort of a miracle, by winning 7/7. Anyway let's see when Ole or other managers will finish second and win trophies, even micky mouse ones.