I think it happens as you say -- sometimes even understandable as a political thread goes above the hundred mark, and few if any have been following it all along.

But I really am thinking of cases more "above the line". Simply stating exactly the same thing as has been stated ... just as if it had yet to be stated.

To be honest, it used to REALLY bug me as impolite. Finally, I came to the realization that the mudcat just works differently -- that more people than not: 1. don't read the thread ahead of their posting, and 2. answer directly to the question as asked in the thread title -- without regard to whether it's already been answered. Here it's not like a group conversation where everyone stops and listens while another talks -- and then the conversation evolves around not just the first question, but the new direction that responses to the initial question direct it. No, here it's more like one person asks a group a question and the group responds to the questioner as if on paper, as if they aren't aware (have no way of being aware) of other respondents.

I've never known why it was always that way here but not on other forums. I used to theorize that it had to do with the Brit/USA split in mores and customs, but, though I theorized that, I couldn't say why that would make any difference.