If it weren't for the long-running convention of using backslashes as escape characters, postfix backslash would make some kind of sense, at least visually.
Forward slashes are for prefixes, backward slashes are for postfixes. Nice parallel there :)
Aside from breaking the escaping convention, slashes in code give the page an unfortunate swirly quality. It seems like line other parallel or perpendicular can make the line of the page look it is at a different angle.
