Contrary to your instincts, it is possible to have too much detail in planning. Life is not a stage play where you have control of every actor and element. You can't account for the randomness of life.
Your thought process needs to be a bit more in the "If-Then" structure, as opposed to the "A-B-C" sequence we gravitate towards. Every moment has a series of possible actions, some more appropriate than others. Choose the one that makes the most sense at that moment, see what happens, then make another choice.
Planning out every possible event response will drive you batty, plus prevent you from doing actual work.