I am not the most experienced on this forum, but something you said in your last post reminded me of my yellow Labrador when he was older. He was the BEST dog ever when it came to interactions. I never doubted him for a minute or worried about him. He seemed to give off this "I'm not going to get into anything with you because you're not even in my league" type thing-- like he was this wise-old sage who could turn a dog to dust in one second if he wanted to. His breeder used to socialize her pups with him.
Anyhow, on to topic, he stood just like that most of the time when meeting dogs who were full of themselves. He would never look them in the eye, just basically straight ahead, hackles up some. Once, we got swarmed by 5 or 6 (I can't remember) 8 month old pitbull pups that a dude down the road had. (He'd adopted the entire litter, god knows why they let him but whatever) They rushed him ferociously--not in a friendly manner; and that was only after I'd had him a year or so, and I'd never seen anything like it. He never moved a bit-- just stood there, staring straight ahead, tail up but still straight, it might've been moving just a bit (or not) and within seconds, the dogs just kind of calmed down and the guy came out and started rounding them up. One of them had really been barking in his face, too. My dog didn't really do anything until the last one was gone, then he turned round to me and wagged and looked at me like "Idiots!"
He may be showing her that he is too old for her and he is to be respected, but in a non-confrontational, mature way.
My .02, which is worth about as much as the paper I wrote this on.