Not trying to start something but.......... I'm sorry, but it is statements like these that make the people from NANFA stay away from this site. Which is sad, because they have alot of knowledge.
As I stated before, Largemouth bass slow down considerably in growth once they hit sexual maturity. However, they do continue to grow for the rest of their lives. There really isn't a max size per se in the whole centrarchid family, just really old fish.
If you want to properly care for your bass, expect 3'. Yes, he might only live long enough to grow to 18", probably less if your feeding him hotdogs and chicken.