RE: What lessons have you learned?
Not enough room to type them all. I will list the most important ones I have learned and some my friends have as well.
Always wear a harness. Saved me from a sudden stop once. The stop would have been the dirt.
Always go with your gut instinct. Cost me a few nice racks and burgers by second guessing myself.
Always double check that you have everything you will need before you leave to go hunting and then again just prior to climbing the tree.
Always go to the bathroom where you can see what you will be touching/ standing in. Rash from poison plants takes a day or two to show up in the darndest places!!