I've read all three events and it is in no way clear whether these events are exclusive to PE, ent_move, or both.

I seem to remember that the same laguage was/is used with ent_move events in the pre-PE days and thus my confusion; if memory serves, a physics entity was synonomous with an ent_move entity.As an example, quote from the manuel:
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EVENT_BLOCK
entity.enable_block
Collision with a surface of the level during a ent_move or c_move instruction or physic entity movement.
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Yet a Physics Entity under the PE would not generate this event by what marco jsut said
The wording is not consistent


The manuel should make clear which events are under the ent_move and which are under the PE.

The way events are presented right now is very confusing.