It’s hard to imagine, that Rumple came back to teach her more after what happened. On the other hand Rumple’s true goal always was to find Bae, and he followed that no matter what. So if Cora’s daughter was the one his glimpses into the future told him to be important and maybe the most likely to enact the curse for him he probably tried nevertheless to keep some influence on Cora, maybe tried a second time to somehow get a hand on Regina, before he succeeded later when she was about to marry King Leopold. I too was wondering about the book of spells, because Rumple said it was his, so he gave it to Cora. Then Regina secretely took it from Cora, after she had pushed her into the mirror Regina wanted to give it to Rumple, but Rumple talked her into keeping it and learn more magic. But when did Cora get the book and how? And Rumple did say, he had Regina in his arms, so there has to be more story (rewatching the second episode of this season, We are Both).
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