A new issue, however, has come up. She doesn't mind my picking up her front hooves (she won't try and yank them away) but she's leaning! She'll start swaying heavily from front to back, eventually leaning so far back that she has to step down onto the foot I'm holding to keep her balance. Her owner wonders if she's actually having balance issues, but I think it's more she's figured out another way for us to let go of her feet. This is happening while she's tied.
Should I go back to working on picking her hooves while she's outside, so if she does that I can send her moving? I do want her to be able to tolerate this while she's tied at some point though. Suggestions welcome!