when a team plays 1-3-1 does that mean the PF's contribution is also added to the Perimeter defense rating?
I think that is the theory that is behind it, but I think the mechanism (the calculation of the ratings) works diffrently.
Instead of splitting up your team in PG - SG/SF/PF - C, and take the first 2 groups for outside defense calculation. I think the team is always taken as a whole, and outside as well as inside def is calculated the exact same way every time (see rules: outside D: guards weighted heavily,...). Then depending on your tactic these ratings get adapted. If you choose 1-3-1, your outside D will get a decent booze, but your inside D rating will get a penalty, as will your rebounding.
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