Maybe there could be two threads and you can't participate in both at the same time. Unless you're answering in one and asking in the other. But I still think no interference is optimal.
If I'm the one answering the questions I don't want the flow to be slowed down. I'm only going to be around so often, so ideally the questions come thick and fast while I'm around to answer them.
There was one point where I made about 4 or 5 posts in a row to ask questions but someone got in first between me posting and hitting post, so I had to wait and see what the answer to their question was and discard my post. Sure it was frustrating in the moment after it happened the third time in a row, but I found it more amusing than anything overall. It's happened plenty of times singly. I don't think there should be any limits. There'll be times when several are eager to post and times when you're the only one around interested in playing. Just let it flow naturally.