On average, double juggling is significantly better than reacting to rooms where only 1-2 options can save you time by not juggling. For example, if your room 2 exit is M2 bottom left, M3 is the only room that save time to juggling. Double juggling saves either losing ~0.35 on 5/6 rngs to react for M3, or a little over 2s on 1/6 rngs.
As far as I know, rooms that would utilize this are M3 side entrances, M2 top left, and M5 as your final room.
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