I purchased a maple slab from a guy who is in the business of drying thick pieces of wood to sell. I mentioned the "year per inch" to him and he said generally if you just have it sitting under a tarp outside that is about the average. But if you bring it into your garage or into your house it dries quicker. He also told me to put a fan on aimed in the general direction of the wood and it will decrease the drying time significantly. He has a number of buildings that look like greenhouses with open doors at either end. He has a fan blowing through them and says a 3 inch thick slab is dry for sale in about 6-9 months.
Just more info to think about.
Just more info to think about.