The concept of this rule just tells me that it's wrong..
meta __TO_NO_BRKTS_MSFT __TO_NO_ARROWS_R && !__TO_UNDISCLOSED && (__ANY_OUTLOOK_MUA || __MIMEOLE_MS)
welcome to 2014 "X-Mailer: Microsoft Windows Live Mail" where is the exception for that? .-) and if you add it so what? even more bloat...