I also think it was part of his plan to get “tricked” by Cinderella and company. If you watch the scene in The Price of Gold, he seems to know she is trying to capture him using magic. I think somehow being in the prison preserved some of his memories as the curse was enacted. Not sure how, but I think it blocked some of the memory wiping properties of the curse.
Good point. I don’t think Rumple cared about the memory because he wrote the curse he could have tailored in anything he wanted. And as far as being in Prison, he needed to be there too I am not sure why yet but like I said he planed out every detail or at least most of it. I do love Rumple. 🙂