I think it’s far, far simpler than that, and no conspiracy about power is required: moving hands attract the eye of enemies, pointing and mimicking movement giv

I think it’s far, far simpler than that, and no conspiracy about power is required: moving hands attract the eye of enemies, pointing and mimicking movement give away elements of what’s being said. Hand signs require visual contact with those being addressed. If you’re behind me and I ask you “where” and you say “over there” and point, what good does that do unless I turn around, take eyes off what I’m doing and ask you to repeat. There’s more overhead involved in communicating that way. I think these are some very practical reasons for it. I also think the advantages of using hands in explaining something (to clarify) may imply that your words alone are not clear enough. It’s an important skill to be able to speak clearly and succinctly in times of collective stress.