A recent example of course is Makfi.I too think SD surprised his connections. And sometimes horses can do that. You’re galloping a big, immature 3yo colt and it’s just going through the motions at home. No sign of anything out of the ordinary. He goes to the races, is green, wins but is still a bit clueless. Off to a much more demanding track like Chester and he struggles early on because quite frankly he’s still not sure. Then the penny suddenly drops mid race. And then he wakes up.
I remember galloping a big fat 2yo colt in the mornings at Santa Anita. Everyone laughed at me as I used to have to sit down in the saddle and kick just to raise a normal canter. The guys on the starting stalls nicknamed him the Pork Chop and would wave as we waddled past every day. But I used to tell them I’d have the last laugh. I just got a spark of something from him and I knew he’d be ok. And then we started to breeze him. And he started to wake up. (And they took me off him as I was a girl! I left not long after but he went on to win over $1m and is the only horse to win 3 SAN Bernardino Handicaps in a row. He’s even got a Wikipedia page! (He was called Delmar Dennis) But my point is that horses can be just that. Seemingly useless at home and aren’t even considered by the trainer.