Traditional event-driven programming often has event priority values or rank, and an optional "end event processing" operation associated with events, doesn't i

Traditional event-driven programming often has event priority values or rank, and an optional "end event processing" operation associated with events, doesn't it? MS-Outlook's "rule engine" has these, for example. That seems the same thing as "allowed to interfere with arbitrary other steps". Sure, you can "lock out" using/modifying such operations, but one must know when and where to lock someone/something out. Programming is still a persnickety endeavor with or without using events.