I try to avoid H&S at all costs, but there have been two rooms so far when I had to check something. But both cases were due to assumptions that have always been true in DROD, and now aren't:
(Contains spoilers for SM, 4E and WG, 2N)
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×SM, 4E - without oremites, Beethro and a mimic can never change their respective sword positions.
WG, 2N - Beethro always drops trapdoors, so that Wubba in the top right can't help and I won't go up there until I've solved this room.