I remember using it in therapy, not to find an exact mid-way point though. For example, if someone is prone to violent outbursts of rage, and they say, well, I'm not sitting here with my thumb up my arse, if my wife is nagging me, and I might say, maybe there's a middle way? This doesn't really mean a half-way point, but something like, 'a way of expressing annoyance without smashing the furniture'. I think people often got the point, and didn't think it was something you could calculate. But maybe with emotions it's rather different, since we don't arrive at them rationally, but we can see them vaguely as a kind of gearing. I mean, I don't have to go into high-octane drama because you forgot to buy the cat-food. Well, the cat might.