@evan In that context, I would expect that the venn overlap I'm describing would be quite large, but it certainly seems like something we could actually measure and experiment with if it were presented as an option.
if Bob replies to a post by Alice, they are implictily relinquishing their communication style to the style of Alice, because it is Alice's top level post. Alice "owns" the conversation as top level poster
Bob must consider the implications of that before replying
that solves the problem
the structure of a conversation is beholden to the imperatives of the starter of that conversation. it should not be hijacked
your other concerns are valid
but are overruled in this context
if i go into your house, i respect the pile of shoes at the front door, and take off my own
the idea there is someone who doesn't understand this obvious thing: i am a guest in *your* thread, is not anyone else's problem
so, yes: some things are obvious
i won't trudge into your house with my dirty shoes. if someone else does, that's something obvious they don't understand they should understand
they can be delicately reprimanded. and they learn. end of problem