No, we can change it. The Admin topic options for moving a thread have a check-box for leaving the "moved" icon behnd called: "Show moved icon in last forum"
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...or...
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...or... ....
As I have said before - it is the Admin or Mods choice whether to leave a "moved" icon behind when moving a thread. For us it is a lose-lose situation no matter what we do - if we don't leave a moved icon people complain, if we do leave one... people still complain. It would be a hell of a lot simpler if people didn't open threads in inappropriate (ie wrong) lounges (ie forums), but eveyone wants their thread in the main Prog Music Lounge.
Out of politeness I will either tell the person who opened it by PM (rare), or pehaps leave a post in the thread saying it's been moved (common), or just leave a "moved" icon in the old lounge (less common).
I've had people get unpleasantly nasty (ie abusive) with me when I've moved their precious threads. Part of the reason for that kind of reaction I'm sure is because active topics in the Prog Lounge show-up on the main PA Front Page where as Get The Word Out Lounge and General Music Lounge do not.
Which brings me to a little rant about "precious threads" - apart from perhaps Prog Blogs, no one starting a thread owns that thread - it does not automatically become "my thread" just because they opened it - all threads belong to everyone equally and once opened come under the control of the Forum Mods - if we want to move it we damn well will, if we want to lock it we damn well will.