When sending a message two posts are done, one to check recipients (javascript:ValidateRecipients()), and one to send the message itself (javascript:SendMessage()), this could have been accomplished by a single post in javascript:sendMessage, since most of the time recipients are correct. Changing this increases the speed in which the code is executed on the client side, (less waiting for server, less code executed), minimizes pressure on the servers (fewer packages sent), and also fixes a couple of security holesv(actually it makes it more difficult to abuse, since you would end up with several lines of javascript) since sending messages is reduced to a single function.