This is interesting. I remember clearly in the very early days with Bramble her keenness to retrieve. A couple of times she pinched Benson's rabbit dummy, and although tiny, she managed to bring it back to me. We then at around 5 months, maybe a little younger, went through the clicker retrieve from scratch. We were at the Glos clicker gundog training weekend. Also, our dog walker followed this to the letter. I do wonder if we had somehow damped her natural instinct down somehow. I don't know though, just a feeling.
Twiglet knocked me over five times due to over enthusiastic returns! She did find her brakes eventually.
It is striking! I find myself shouting 'Brakes! Betsy! Brakes!' as she slams into me at a full gallop....apart from when I'm asking her for a hand delivery....I think I'm just going to quit that, and live with her circling behind me for a bit....
Rourke used to crash into me and then when older discovered that he did have brakes. I do think they learn themselves as they get older.