I think he might have been referring to the way i use it -- to obscure the gender of my partner. this is not because I'm hiding it. rather, it's because i'm avoiding the heterosexist assumptions built into words like husband, wife, etc.
personally, i was non-committal about partner. years ago, i used boyfriend/girlfriend. but eventually, this made no sense and partner grew on me because that is precisely what we are: partners in crime, partners in our latest day trip, partners in learning, partners in exploring, partners enduring inclement economic weather. it evokes, for me, so much of what we've found ourselves doing: holding each other's hand, ducking our heads together against a driving rain, and forging on through the storm ahead. partners. sharing. and now, more often, partners in discovery, adventure, or even just partners in sharing an afternoon together at the library and a walk home in a misty rain.
now, i miss it and, although i could avail myself of mi marida, i still prefer partner because it conveys something about what we've been through together, which yes does include being in business together.