Board Thread:General Discussion/@comment-24674051-20150420171129/@comment-25926288-20160318111640

Rwo wrote: Zelena also used magic to curse Hook while she was in disguise as Ariel.

However, Regina had enchanted Hook's hook to rip only one heart out, which he did with Aurora's. When he tried to rip Zelena's, it was thanks to a potion of Regina's, not directly Regina's magic. It was Regina's magic. That is why Hook was able to take of the cuff...at least to my interpretation.