In watching the Mad Hatter episode and realizing that Rumple and Regina made a deal I am wondering if the deal includes Belle. I think he knows that she has Belle, and I think that Belle remembers everything and this is why she is locked up, after all believing that you are Belle from Beauty and the Beast is crazy. Remember how Regina went straight to the psych ward after she learned that Rumple knew who he was? I think Regina set up the deal of Snow White/MM for Belle. Just a theory but I think that Rumple is way to smooth to loose it on Regina. I think he knew a long time before he even gave Regina the curse that she had Belle, and is partly why he created it. After all Snow White begs Charming to take her to see Rumple when she is pregnant because he CAN see the future. He has the advantage of knowing what is going on when nobody else does. Just my two cents.