As I said in this sunk thread:
I find thread sinking very disturbing.
If it's going to be done, I agree with Phil and others that at the bare minimum a notice of a thread's sunk status should be issued.
IMO, this thread sinking addition is by far the most negative aspect of the new forum.
Here are two threads I'm aware of being sunk.
The previously sunk thread has been sunk again.
And this one:
I don't think it bothers me that either of these threads have been sunk; what bothers me is there's no notice of the thread's sunk status.
All this sinking is making me feel like abandoning ship.
Adieu Parallax's Forum.