To all the people with the little and big todo lists, live a little. Let life surprise you.
I guess that´s why many people don´t even start with trying to implement GTD into their lives. They fear being "too organized". What many people don´t get is that after "clearing your head" and really using GTD you have more space in your mind to actually live and be creative.
If you can't work because a dog is biting you in the leg, one response is "I'm too busy to fight with a dog right now, and fighting with a dog isn't much fun, so I'll just ignore it and focus on my work instead." Not sure that's the best path to productivity.