No need for double posts...you just need patience. Post it, then ignore everything else. Don't repost...just keep pressing 'leave the page'. It's a war of nerves between the site and a human being...the human being should win.
I know mate, it was ridiculous. I even went away for a while, after copying my post, and came back sometime later and pasted into the reply box, and the problems were still there. When it finally went through I couldn't believe how many posts there were. I was sure there would be a maximum of about 6. Then, of course, I tried to get rid of them and could manage one only. The rest stayed resolutely there even though I'd marked them all for multiple deletion. The server was in such a spin that I realised the best thing to do was give up until later. I notice your comment ended in a double post..!