Only mentioning this as it came about as a result of various user requests at the Annexe, i.e. different members of Mudcat prefering different things.
We just give users a choice how they would normaly want to open a thread from the forum page and build the links in the thread listing accordingly. It's not perfect but it overcomes the sort of problem John mentioned.
Where last post first is used, we carry a balance of up to 9 posts from the previous page. This is to try to reduce the need for users to go back a page to see if anything has been missed - quite likely when the last page only contains one or two posts.