The WTBTS is never going to settle on anything final. Why? Because then no one would buy their literature. Every Witness and by-stander buys every single piece of trash these guys publish because no one wants to be left behind. For instance, what if a dubbie missed the Witchtower article on incense, and was subsequently caught firing up the ol' Nag Champa? The consequences would be staggering! He might even stumble someone!!!!!!!!!
Ever-changing doctrines guarantee millions of sales, in addition to however many they manage to unload out in service.