I like controversy so I chose to make my rule about gender and pronouns/ word choice. The rule/s I am adding to can be found on p60 of Strunk and White's The Elements of Style and p 34-35 of Williams Style .
"Never use a pronoun such as he or she unless 1. there is one subject being referred to. 2. and it is known the gender of that subject or 3. if multiple subjects there is only one gender, such as the women. Otherwise use they or their. And for words like policeman or mankind, substitute them with words such as police officer or humankind."