For Manchester United, it is difficult to see how their first game of the new season could have gone much better other than perhaps another goal or two to polish up their superiority. As it was, they shouldn’t be too greedy. Romelu Lukaku has wasted little time demonstrating why he became the club’s most expensive summer recruit and, on this evidence, it is shaping up to be a season of rich promise for José≈ Mourinho’s…