Our defense has been so bad that it has even silenced some of the folks who say it makes little difference (not all of them , I would note).
One thing that is not "arguable" is that the real key is the run differential, i.e., runs for and against. Over the season Mr P's theorem is almost always on target, in terms of W/L. The "for and against" is surely highly dependent on pitching, also, so defensive performance is difficult to address separately.
The problem for managers of a team like the Tigers seems to be trying to measure the trade off that occurs between the offense and defense offered by various players, that is, how they would affect the differential on the bottom line. Some can hit but not field, some the other way around , some can do neither.
Overall it has turned out that Miggy and Prince in the end , are a plus -although they would be more of a plus if Miggy played 1st and Prince DHed. Jackson is surely a plus, Jhonny and Avila about neutral, while Berry still seems to be a bit of a plus despite his fielding problems - a plus that could deteriorate over time. Thing is his speed has given them much better run scoring.
The rest of the group: Boesch , can't field - up until now hasn't hit, Raburn, can't field -can't hit, Kelly, can field -can't hit, Ramon fielding OK but deteriorating, hitting below average, Laird, good defense, hitting above expectations.
No matter who we put out there we are pretty bad defensively. With some combinations we are just plain awful.