yup, from a treestand I always shoot sitting. If I stand its only to take a break and relieve the back strain. It is important to use maximum patience and wait for the right shot. Success will only happen when you do everything right. I'm am glad that you are self analyzing your mistakesa as that says you are dedicated to improving yourself! The last concern you should have is can I make the shot when it presents itself. That becomes somewhat automatic from lots of practice. You're on the right track, good luck.