The article doesn't mention that Jamie Vardy is the third-highest scorer in the league, which combined with brilliant individual performances from Mahrez (just awarded the PFA award for player of the season), Kante, Drinkwater, Huth, Morgan and more, has seen some superstar performances that have made a real difference against teams that would have been seen as superior last season.
I'd suggest that Ranieri's success as manager has been as much to do with man-management as tactics. He was very careful to get the team focused on staying up, on getting 40 points to survive. It was only in the past few days that he told his squad to go for broke and push for the title. They responded by beating Swansea 4-0, despite being without their top scorer.
The Leicester tale is magical, and incredibly unlikely, but I would challenge anyone who said that they don't deserve it.