Tried this and it never worked, later now i know why because manager speaks to me (human) whereas i have to speak to computer(no margin for ambiguity). The best thing is to be polite, listen and be humble and think yourself as a object flowing in the river. Never show anger a slightest bit. But once the attack starts personal, just ignore and look down as speaking to a complete idiot. This is not the best thing but it has worked very well for me.