I just saw that I've exchanged the letters!
Of course, when A attacks B, I'll start training with B, the victim and not with the attacker!
But it's an interesting point you're having there, because I wondered something similar myself often too. Generally, it's Blacky, when I'm training him, who attacks Sjors. So I immediately start training Sjors. But Sjors is a very sneaky and sly pony, and even though he does 'nothing wrong' when he is being attacked because he just stands there looking at us or slowly walks towards us, I can't help wonder if he isn't being rude in horse-language to Blacky. He did something similar when driving them both in a team as well, with very subtle nastiness getting Blacky to attack him, and then have me correct Blacky for attacking Sjors.
Those attacks continued no matter what I did to try Blacky to stop doing that, right up to the moment that I decided to instead correct Sjors with one slight slap of the whip as soon as he looked at Blacky in a slightly foul way - He got sooo angry at that! I can't help but suspect that most of his anger was about being found out, because he did it two more times and then it stopped and Blacky never attacked him in front of the carriage anymore.
So training two horses already is quiet something, but if one is a potential evil genious, it's quite a challenge indeed!
I should have known <slaps forhead with hand>. I thought, knowing you, that the A to B sequence was totally incongruent with your thinking. And I assumed a training error when it's much more obviously a typographical error in writing.
I wonder how many people would catch the subtlety of the "setup," as you describe it?
When I worked with emotionally disturbed children I observed again and again when a group disruption occurred, that the quietest child in the room was in fact most often the real instigator.
Masters of the lifted eyebrow, the subtle turn of the body or appendage. The artist with the seemingly innocuous comment, reading the others and picking not just the right insulting comment, but the exact second to deliver it.
Fascinating that you pick this up with your horses.
There is nothing so frustrating as the passive aggressive manipulator, and you I think you have identified one.
My best guess as to your question about Sjors being rude in horse language?
Well, horse's speak to each other by movement and proximity as well as direction and speed of approach, and body attitude.
In fact, slow approaches, coupled with body posture can be a much louder 'insult,' via threat, than and all out charge. Lead mares are elegant with the "slow threat."
Horses also read subtle facial expressions.
A whole herd can transmit anxiety by one starting with that tight skin round the eye look.
A little wrinkle at the corner of the mouth.
More subtle still are the combinations communications. Head up, tight eye skin, one ear swiveling. It gets MY attention when I detect a horse doing it.
So tell me, what do you think a horse kicking at its own tail means? That's one that I guess has to do with anxiety, but darned if I feel confident in that simple an answer.