I could be wrong, but I feel that, at their best, when their players are playing to expectations, the Thunder are the better team. When the Thunder are doing strange things like Harden sucking, Scott Brooks biffing substitutions and player match-ups or the team shooting free throws below their expected rate, Close games can tilt to the Heat's favor. Especially when you get historically good 3 point shooting from Shane Battier or 25 points on extremely efficient shooting from Mario Chalmers. Miami's perimeter defense, especially Battier and LeBron's ability to deny Durant positioning in his comfort areas, has been the equalizer and then the various unpredictable factors that come with short series like Snayke mentioned has been the difference imo.