I find my focus on writing here and elsewhere depends very much on whether or not I have something I feel I really want to discuss or even pour out. Often I can become jaded and annoyed with my own lack of progress so I look for diversions for example the answers section you mentioned. The act of doing something different allows me to go back to what I was doing or writing feeling refreshed. Once back I just start and allow the writing to take me. But ultimately it will only work if you really want to write what you are working on, if your not interested getting focus can be very difficult.