My contention is that there is some luck when it comes down to a handful of plays to determine if you win or lose. Good teams make sure it does not come down to that often, and that is why they have better records.
Essentially, my contention is this: we put more value in winning close games that we should; we should instead rely on MOV, and wins based on "stomping" your opponent, to determine championship chances. The following study supports my argument:
The Miami Heat have been under fire recently for dominating weak foes and losing close games against good teams. The conventional wisdom is that this reveals a major gap in Miami's armor -- they just can't close the deal against stronger opponents.