Nice post, full of lessons and reflexions, and thanks for the final lessons!!
Powerfull part:
"I hope that there is something that you can take away from this post, and I hope that you remain humble and teachable. I know that I'll have to, or these things will take me forever!
I think that the main reason people say "you can't teach an old dog new tricks" is because of the mindset of the dog. If we want to, we can learn all sorts of things no matter how old we get, and there is no reason not to."