Unidentified gait object

There are three gaits:  walk, trot, and canter.  And gallop and tolt and jog and rack and pace, but whatever.  In the dressage ring, I worry about three gaits.

Well, not really, because there's working walk and free walk and collected walk and extended walk and medium walk . . .

Okay, I only have to worry about five kinds of walk, five kinds of trot, and five kinds of canter.  Which is a heck of a lot more complicated, since that's fifteen different gaits.  And how does one differentiate between them?  Hell if I know, I'm just a recovering h/j and eventing rider that's still struggling to remember where the letters go.  Seriously, where the hell is L?  As far as gaits go, if it's got two beats and rattles my teeth if I try to sit, it's a trot.  Done.

But today I had something rather unidentified show up.   Normally an unidentified gait is a bad sign, but Trainer A seemed quite excited by the appearance.  I'm trotting along, holding my wine glasses as instructed and managing my duct tape (all visuals, much the pity, I ride better with a bit of wine to mellow me out) while encouraging mi papi to go softly forward with an actual correct bend for once when I realize I need to circle to let the horse in front of me finish the line of cavaletti before I go.  I circle around at about ten meters, give him a upward half halt as we straighten to correct the balance , and all of a sudden he just . . . went weird.

Like, not expecting me to carry his head, but still on the vertical weird.  Like, slower tempo but deeper bounce weird.  Like able to keep him straight with my legs weird.  Like not speeding up through the cavaletti weird.  Trainer A started chanting 'keep it, keep it, keep it' so I just sat there, not moving, while he went over the caveletti.  Because seriously, what was this foreign thing going on?

And he just kept doing it!  All the way around the ring and back over the cavaletti, so long as I held those wine glasses, kept my elbows in, kept my bear down, kept off my pubic bone, and kept my calves against his sides.  I wanted to put my hands down to find that familiar drag so badly, but she kept telling me to pick my hands up and not mess.  She liked it!

So I'm still not sure just what gait that was, but I'll tell you, recreating it two more times in the lesson had Trainer A quite content.  Mi papi also seemed quite happy to find a spot where I'm not mucking with his mouth or poking him with my spurs.  Oh, and where I hold my hands like a serious business dressage rider and don't drop down to find him when, evidently, he doesn't really need me anymore.

Was that, dare I say it, actual collection?  Because if it is, it's freaking weird.