If your boss has a different plan than you do at the beginning of the week, you may just have to suck it up and do it their way. Bargain to try your approach next time, and provide backup about why it'll exceed expectations. On wednesday or thursday, however, you'll be happy to have their leadership when you need it most. Don't forget to tell them you value their support and mentoring. Then, on friday or over the weekend, you'll get a chance to give back in the form of offering help yourself. Now that's some good business karma.