The thing is, if the Thanks process is running in the background or in a small region of the page it doesn't matter whether it goes slow. The user can keep reading without interruptions. If the page reloads there is nothing that can be done apart from waiting and eventually searching again for the exact place where you were reading.

Actually the talk.maemo.org theme doesn't reload the page and shows my thanks after a little while (but you can continue reading the page in the meantime. So perhaps you can borrow that piece of code?