No, water being absent from tobacco doesn't hurt anything, but when it comes to drying down past losing essential oils of the leaf, then it starts to become tasteless. But, what causes tobaccos to lose these oils is more abstract. It's not just drying. A tobacco can be hydrated, but still lose oils.Does the tobacco really lose anything by being dried that long?
99% of what guys think concerning dryness and staleness of their tobaccos is mostly psychological.