That's right. For instance, BAVG and/or OPP BAVG are not predictive in nature. Then if we are comparing team stats, how do we treat teams that play in pitcher parks (OAK, SEA, etc)?
Bottom line the 2013 Detroit Tigers were not the offensive juggernaut many believe. It was done with smoke and mirrors. If Team A, hypothetically, scores 50 runs in 10 games, but three were by 10 runs, two were shutouts, that leaves 20 runs in 5 games (4.0 R/G). Now, Team B also scores 50 runs in 10 games, but does not score 10 or runs in a game, and only gets shutout once, then it is 50 runs in 9 games (5.6 R/G). Which one is the consistent offense? If that trend continued all season long, both teams would finish 1 and 2 in offense. But that is generally only due to counting stats.
I am not the best at stats, but all my research (I have been doing baseball stats for about 40 years) refutes the mantra "pitching and defense" wins in the playoffs.
If you have a Jekyll and Hyde offense, was it the offense that made you lose? Or was it the opposing pitching? People who believe in pitching and defense will say pitching. And in some cases, it would be hard to argue.