First of all, you should be doing this under your psychiatrist's supervision. The minimum taper they use is generally six weeks, but different docs use different tapers and most aren't very clued in about it. The best answer I've seen is, it takes as long as it takes. I wouldn't risk a fast taper personally, but I'm not you. If you're quick cutting down so far has produced no withdrawal symptoms, that's a positive sign. But this stuff can hit you after you've quit, so you just never know. But again, it's your life, if gaining weight is worse to you than the risk of a horrid withdrawal, then go for it. If it's not, then don't. Hope you have an easy one.