If I'm struggling I will quit at eleven and go to bed to think. Now, if you are asking me how often I write without sitting down at the computer then I will have to say that I am writing most of the day. For some reason, I write in my head more on Saturday morning, in bed, than at any other time. I realized early on that even a great idea can be lost if not written down. I carry a wallet full of notes.
Good writing is an art, regardless.
Writing fiction, I believe, can be taught up to a point. I do believe that fiction writers, the ones who write as an art form, are born. There is something in the mind, a whirling mind, that does not seem to sit still until the information is gleaned and put down on paper. Your mind operates under a tremendous imagery. It's hard to explain, really.