I can only see the latest responses on threads if I click on the relevant topic again, just before posting a reply. If I take a little while to compose an answer, I can't see replies entered since then, so my responses may well come over as offensive or silly.
We've all fallen foul of posts sneaking in before we press submit!
I tend to open another copy of the thread in a new window and refresh it just before I submit my post in the first window, thus enabling me to amend my reply or scrub it or whatever.
This method is not foolproof though since someone can still post in the second or so it takes for the post to get through.