I like how Jack has documented his own experience. It helps others as it helps himself. I have many years of books (diaries) of what I did day by day to improve my health. It really helps to be able to look back to learn even more about what we do right and what we do wrong. People always think they will remember...but sometimes the answer is buried in the details that really teach us something important.
I'm wowed even if he didn't make it to 120. Like Rainy says..."just stay safe"...especially if you are a very goal oriented person.