I want so bad to go off on a rant here, but will bite my tongue for the sake of dignity.
All I will say for you people wondering about the coexistence of the defroster and a/c is answer this question, "Why would vehicles come equipped with a defroster that only flowed cold air." My God are people that dim? Have you adjusted the TEMPERATURE control for warmer air with the a/c? Guess what happens, IT GET'S WARMER! AND THE A/C IS STILL ON! Imagine that.
Oops, dove into rant territory after all.