I always appreciate those who cite quantitative data, as long as they don't discount qualitative data.
Many factors beyond just chance can determine outcomes between two good teams in the postseason. Some of those aspects can include head-to-head records, and who's hotter, healthier and hungrier; the latter Hs often combine to form the concept of momentum -- which may just be late-season additions at the trade deadline or rookie call-ups (whose young, supple muscle tissues have an advantage over more brittle veterans on cold October nights). Exhibit TB: Randy Arozarena.
Many GMs talk of increasing their odds by constructing rosters "built to win in the postseason" -- so there must be something to it. For those of us who remember the '88 and '90 seasons, the Red Sox were clearly overmatched by the mighty A's. But while Boston couldn't win one single game vs. Oakland, seemingly inferior teams like LA and Cincy pulled off major upsets by dominating.
How? Are we overanalyzing? Does the old adage Good Pitching Beats Good Hitting still supersede all other theories?