Obviously, the bbs lags at times, we've all experienced it. When you hit the post button, it just sits there in an almost infinite stalled position. The natural thing to do is think something is broke, backspace out and resend it. DONT!
After you click post and it starts lagging, just open up a new browser window to browse other stuff and forget about it. Let it do its thing. Even if it takes 10 minutes, it will post your reply.