It's an interesting and eye-opening study into poor refereeing for sure, but to say how it directly impacts clubs like they have shown is still probably not accurate. Where they say we'd have had a 1-0 win if we'd have been awarded the penalty against United instead of a 0-0 draw and then finished second instead of 4th etc...is only the maths. If we'd have had the penalty, maybe we miss it. It doesn't guarantee a goal. And lets say we do win, Mourinho was playing timid and got the result he wanted, but if we score then maybe he opens it up a bit more and they draw level, or even after the equalising goal then fancy themselves to keep attacking and go on and win it. The botched calls are frustrating, but this study just looks at the numbers, it doesn't necessarily take into account that the entire dynamic of the match will change after a goal.