It's a minor annoyance - I often click on a thread I've just read because it looks like a new thread. The solution, as Bugsy pointed out, is to avoid clicking on messages by certain people. No offence intended - it just keeps me from swearing. ("Sh*t! I just read this!!")

Of course, I probably wouldn't have clicked on the White Hare thread again (at least not for a while), but my name was in the new title.

You can also check the thread number, but that normally is too much work.

Also, if the link is the same color as a visited link, you've read the thread.