You mean the topic is same but there are new or interchange idea but it still revolve on same topic right? You'll likely found a lot here in forum. What could we do? Some are like improving or showing their best opinion on certain topic. Actually it's not bad, as long as the first topic lacks the one that the new one that is being discussed. Or the first one is being abandon and needed an active thread for that. There are catches with it but there are moderators to oversee these. No need to worry about it. Plus you can do reporting if you noticed post like these.