When interpreting baseball stats, I would consider the following checklist of what the stat includes:
- Batting, fielding, or both? (WAR is both unless you look at oWAR/dWAR separately)
- Counting stat or rate stat? (WAR is a counting stat)
- Is there a park/league adjustment? (yes for WAR, yes for OPS+)
- Is there a positional adjustment? (yes for WAR, no for OPS+)
- Is there a replacement player adjustment? (yes for WAR, no for OPS+)
So the formula for WAR is actually quite simple:
WAR = (Batting Runs + Base Running Runs +Fielding Runs + Positional Adjustment + League Adjustment +Replacement Runs) / (Runs Per Win)
(runs per win is basically the 'year' adjustment)
With WAR I think you have to first buy into the idea that a player's value is best quantified by runs created / runs prevented. Preventing runs is probably the more interesting one since some positions have way more opportunities to prevent runs than others, and DH can not prevent any runs at all.
So if you're going to dream up an ideal baseball player to maximize WAR, it's probably a CF who gets on base a ton and hits for power...Mike Trout. It would be impossible for Trout to achieve his lofty WAR total if he was playing 1B, as it should be since he can't prevent as many runs at 1B and it's easier to find a 'replacement player' at 1B to generate decent offensive production.
By that logic, it stands to reason that an OPS of .850 is far more valuable at some positions than others.
I think of Chris Carter's 2016 season as an example of where these park and positional are so valuable in quantifying value. A 1B with poor defense and a low OBP isn't that valuable even if he hits 40 home runs.