It really is just another way of phrasing "is this sexist?" for most people.

In some cases, yes. In which case I think it's still imprecise language, but most language is so it's not a big deal :)

But sometimes people really do use the "Either I'm not sexist and this behaviour is ok, or I am sexist.. but I can't be because some of my best friends are girls (or whatever). So the behaviour must be ok" argument.