Jose Mourinho was in charge of Manchester United for two and a half seasons. The veteran coach made the acquisition of players like Paul Pogba, Romelu Lukaku, Alexis Sanchez and Nemanja Matic, and then proceeded to implement nothing other than his completely defensive strategy. Now, for the first time since his departure, the United players are experiencing what it feels like to play in an offense-heavy strategy under the new coach and former Red Devil, Ole Gunnar Solskjaer. United's performance has improved by leaps and bounds after getting rid of Mourinho and with the new, less strict strategy. Nevertheless, one must not forget that Mourinho was in a fight with the titans and he was aware of that. That is why, although extremely unsuccessful, he insisted on his purely defensive strategy. He knew that the fight for the Premier League cannot be won with opponent analysis only - something Solskjaer is doing right now.
I think Solskjaer uses the element of surprise very well because while he has been won five games in a row at the helms of the club in just over a month, no one understands what his strategy is. Thus, almost all the sides that faced Manchester United, including Tottenham, had no clue about what kind of a team they will play against. The Red Devils scored an average of five goals in Solskjaer's first three games in charge while that average came down to only one and a half in the next two games. Unlike Mourinho's United, Solskjaer's United is a complete mystery, but that alone cannot bring long-term success. A team in the Premier League must have a grand strategy like Pep Guardiola's Manchester City and Jurgen Klopp's Liverpool. Therefore, I do not think Solskjaer's rapid success is sustainable; there will be a time when Manchester United must return to basics, and create a team like Manchester City and Liverpool.
At this point, one should not be pessimistic, both Guardiola and Klopp failed in their first season and Maurizio Sarri and Unai Emery are also failing to some extent in their first seasons. It is a natural process of football to lose while building a new team. The more important problem is this: Is it going to be worth it? In Mourinho's case, it was not worth it. He insisted on his old school defensive strategies while his opponents interpreted the game in a completely new and holistic way. Solskjaer should be aware of that and should not try to fall into the same trap as Mourinho.
I think Manchester United has the right squad to play like both Manchester City and Liverpool, or Chelsea and Tottenham. The priority should be creating a plan that dares to play a grand, repeatable strategy and face these giants in their own battlefield. Manchester United should not submit to the role of a second-class team in the Premier League. I am aware of the fact that Solskjaer is trying to boost the morale of the team and is not giving players orders that they can't deliver. However, this hybrid system cannot hold forever, and there will be a time when Manchester United will need to bear the pressure again.