If watching this page/thread, do you get notifications where applicable? (by e-mail)
That sounds like a bug if that changes the watch state of the parent page.
If you click on the from part of the a fragment of a discussion from User talk:KTucker (meaning the User talk:KTucker part of this example) you will be taken to the Talk page. If you click on the tab to the left of the Discussion tab (which might be Page or User depending on the namespace) you are taken to the parent page that the Talk page belongs to. The Watch/Unwatch setting is beneath the disclosure triangle to the right of View history (or has a tab heading to itself if you are using the old Monobook skin).
Thanks Jim - I now see that changing the watch status of the 'discussion page header' has the same effect as changing the watch status of the "parent" page (and vice-versa).
So, watching the page will result in notifications for all threads (watched or not). That's a feature, not a bug, fine by me :-). It saves having to specify which threads to watch (I usually want to watch all of them if I am watching a page).
If one wants to watch only specific threads on a discussion page (not all of them), then don't watch the page itself.
It is the If one wants to watch only specific threads on a discussion page (not all of them), then don't watch the page itself. part that I don't believe works correctly with the current version LiquidThreads. I have never gotten it to notify me on an individual thread.
(I think the current LQT actually "watches" a particular posting, and not its replies... so it is not useful for watching a thread.)