...I would have just posted a link but everytime I go past the first page it transmogrifies into another thread. Maybe moving it up the pile will sort out the links.

I don't think so, Jo. I find that all cross-thread links behave that way. They're OK when I view them in threaded mode, and the first page is OK in flat mode, but if I click another page number or Show All in flat mode, I go to a completely different thread as you found. This applies whether the link has been referred to with showflat.pl or showthreaded.pl in the url.

Can someone with a better understanding of HTML and browser behaviour provide an explanation and/or solution?