Partially the reason why I don't grow and buy my tobacco. Even 6 months makes a difference.Bob sent me a sample of two different dark air tobaccos from India. He told me he had only ever used very small amounts because they were very strong.
Well, I smoked it all. It was easily smoked, smooth, and not high in nicotine. I think the years of sitting in storage, no kilning, no special technique at all, caused it to get significantly better in all aspects.