He did do well based on the results. A lot of things happened with some financial restrictions from the board, some keyplayers who had to be sold, etc. It was not an easy year for any trainer who would have had his seat at PSV from that point of view.
However, football tactical and technical wise he didn't do well at all. There was for example not a clear vision in how to play. One match we would press very high and aggresive, another time we would try to dominate and control the possession game. There were also enough matches (most of them) were we would play an old fashioned kick and rush or catenaccio style of play. In modern football this doesn't work. You have to have a clear style of play. Characteristic was an interview in the beginning of the season were he said he wanted to defend like Simeone and attack like Bielsa. You don't have to be rocket scientist to understand that those are two completely different worlds of football which you cannot tactically combine.
And all this was furthermore amplified by the fact that a lot of Ruud's tactical principles were outdated. In possession everything was very rigid. There weren't much vertical runs, the positional formation was very rigid with hardly any rotations, no use of halfspaces, etc. Defensively everything was man-marked which made it easy for opponents to dismantle our defensive structure using simple rotations and runs without the ball. During the whole season, every match there were phases where the length between the striker and last man during pressing/gegenpressing/transition was around 60 meters.
Eventuallty this lead to the situation were a lot of players didn't take him seriously because tactically he wasn't up to the job. Some influential went behind his back to the board to say this could not go any further like this. The board also didn't have a lot of trust in Van Nistelrooij which eventually lead to his resignation. The reason he got the job in the first place is a bit vague and there are a lot of different rumors. What is clear is that the former general manager (who didn't have a lot of football knowledge) clearly had a prejudice for ex-profs from the club instead of measuring people based on their qualities. It is for that reason in the first place Van Nistelrooij got the U19/U18 job and a few years later the U21/U23 job, while it was widely known on the youth side of the club that he wasn't up to this task at all.
A lot of people who i spoke who worked at the club or worked with him, described him as an amazing person but tactically insufficient with a capital letter. It surprises everyone that he is in the conversation for a manager role at Burnley and it seems to do more with his iconic status and name in the football world than rather with his qualities as manager. It seems to us that this is also one of the reasons why he is getting this job as an assistant. Although, I have to say i think the role as an assistant suits him more than a manager role in modern football. Yet he still needs a lot to learn.
