Mourinho has set up the team to counter that he does very often. He hasn't really pulled a rabbit out of his hat here. Leicester are struggling because of their own naivety and of course Harry Kane's brilliance. There is no way Spurs can win league titles with this type of football against teams like Man City and Liverpool.
For a one off game, this style of pragmatic, low-risk, counter-attacking football works when the opponent makes more mistakes than you. I am not complaining as he is doing us a great service and maybe inadvertently paying back all the millions in wages he has taken from the club.