So when you think about the 19 Dysfunctions that we discussed and succinctly working on them like the Arrowsmith School does I related this to exercise. As we get older it is more difficult to "shape" ourselves physically. Also, as we grow older it can be more difficult to learn new tasks. The brain is still plastic it just may take more effort to exercise it and you may need to be more focused (i.e. meditative) about it.
I just wanted to get that random thought recorded, before I lost it. Now I better hit the treadmill.