No special considerations required. If you have only one booster there is no issue as there will always be a path for current to flow from rail A of one power district through the decoder and back to rail B on a different power district, unless a protective breaker has tripped. Ditto for crossing A-R boundaries as a short circuit will be created by the first trucks to combine opposite rail polarities together, causing the A-R unit to flip and correct the problem. If you have correctly installed the power common wire between multiple boosters there will still be a path to power the loco when drawing power from rail A of booster 1 and rail B of booster 2 when a loco crosses those boundaries. This is one of the several reasons to provide that common bonding wire.
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Trying to think through what would happen if such a skewed pick-up engine crosses from one power district into another, or into an auto-reverser. It's giving me brain freeze. Any special considerations there?