So if this tea thing happened at (nearly) every meeting, you'd have been able to discuss the issue in private, between meetings, and offer to raise it next time--or probably better, discuss it, let her know that if she'd bring it up you'd have her back?

I don't know actually--apparently she had an idea of something she would be comfortable with to address it? I have some ideas for different approaches which I wrote down but then deleted because in the end it comes down to what she feels comfortable with. <-- this is actually not a male/female thing, but applicable in any social situation where you intend to stand up for someone getting the shitty end of a stick.

Anyway my point is, I'd almost always first discuss this with the person in question rather than speaking up in the heat of the moment. It's usually not appropriate, puts the person in a tight spot or a spot light and sometimes these things are better resolved at a different, quieter moment anyway. The exception to this (for me) would be when a remark is really offensive or not subtle at all (like the low-cut blouse remark in the article[1]), simply because at that point it offends me as well, even if the person isn't even around because I shall not tolerate such toxic remarks in a place where I have to work.

[1] "Hey Jim, your fly is open! I KNOW WHERE I'M SITTING! :D wink"