Yes and no. Yes, violent stranger rape is a tiny percentage of rapes, but the communication thing is (according to a study by Lisak) largely a post-hoc rationalisation; at the time communication is actually quite clear, but because of this myth, pretending to misunderstand etc proves an effective form of plausible deniability. Alcohol, yes, definitely, as again it's just another cloak of plausible deniability and 'social license'.