I'm okay with collaborative posts except that they end up being too wordy that a lot of folks kinda gloss over them. I know some folks have glossed over my own word blocks.
I do actually prefer posts be collaborative just because of how fast and reactive some duels can go, and waiting a post will in fact cause confusion if someone wants to chain to activation. So I'm going to say that if you're going to collab post, make sure the actors at hand are all clearly distinct from one another (color code or something). If otherwise, I expect everybody to be fair- as in if someone wants to chain a trap or quick effect in your post, you should let them.
Edit: Also for ease, I'd think it'd be beneficial to post game status in a little hider at the bottom of each post (Turns passed, cards in hand, cards on field, cards in grave, cards banished, cards in deck, etc.)