The odd times that I've done splits I always worked the posterior head (rear) with my back and the anterior and medial (front and middle) with my chest. worked good.
talk to ya later
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Ditto. Alot of back movements will hit the posterior delts (eg rows) and alot of chest movements will hit medial and anterior delts, particularly anterior (eg bench press, incline bech press), hence doing them separatly when using a split.