Well, here at threadsdev, when you have threaded mode selected, and you choose expand, then the links to the individual posts are in threaded mode.
I found a bug though:
The desired behavior is that when you click on a link in the expanded list when displaying posts in flat mode, it takes you directly to the post.
It doesn't do that though, since the syntax is wrong in postlist.php
Fix:
in postlist.php
search for:
$postrow[$z]['goto'] = "#$PNumber";
Replace with:
$postrow[$z]['goto'] = "#Post$PNumber";
Search for:
$postrow[$z]['goto'] = "#$Number";
Replace with:
$postrow[$z]['goto'] = "#Post$Number";