Dear Taffy, You’re not a candy. You’re a dental payment plan wrapped in wax paper that may or may not have been recycled from someone’s discarded floss. During the post-summer sale, I bought two boxes and received one complimentary box of cavities. A three-for-one deal, and only one of the three is free. Every year, I swear I’m done. Every year, I’m proven wrong. You’re less a confection and more a dental booby trap, half nostalgia, half gum graft. I spend ten minutes every winter prying you loose with the determination usually reserved for removing windshield ice. Still, you’re hard to hate.…