Hmmm. where do I begin.
Thanks for the research, keep it comming,I am very cruious about your ideas and conclusions.
As you mentioned, 13 is way too small of a sample.
It might be said that the team with the lowest record going into the playoffs is the better team.
I'll use the football example of the NFC in the 1970's. The NFC was divided into three divisions; East, Central and West. Each year three division winners and a wild card would compete in the playoffs to see who would play in the super bowl.
The toughest competition was in the NFC East; where two to three teams would battle for the playoffs every year. In the central and west divisions, their was usually one team who was clearly superior(usually the Vikings in the central and the Rams in the west).
Because the competition in the West/Central was so weak, the winners of these divisions would usually have the better records. However having the best record did not lead to championships
Of the ten NFC champions, 6 came from the East, 3 from the central and 1 from the west.
In fact 8 out of ten years a team with the best record, or tied for the best record, did not win the NFC championships.
My point; the winner of the strongest division is the best team. If that team's playoff record is less then 25%, there is a flaw.
Check out the division champion from the division which has the highest number of victories for all four teams. Compare it to the winners of the weaker divisions. Your math guys, figure it out