Kazuo Ishiguro in The Guardian:
Many people have to work long hours. When it comes to the writing of novels, however, the consensus seems to be that after four hours or so of continuous writing, diminishing returns set in. I’d always more or less gone along with this view, but as the summer of 1987 approached I became convinced a drastic approach was needed. Lorna, my wife, agreed.
Until that point, since giving up the day job five years earlier, I’d managed reasonably well to maintain a steady rhythm of work and productivity. But my first flurry of public success following my second novel had brought with it many distractions. Potentially career-enhancing proposals, dinner and party invitations, alluring foreign trips and mountains of mail had all but put an end to my “proper” work. I’d written an opening chapter to a new novel the previous summer, but now, almost a year later, I was no further forward.
So Lorna and I came up with a plan. I would, for a four-week period, ruthlessly clear my diary and go on what we somewhat mysteriously called a “Crash”. During the Crash, I would do nothing but write from 9am to 10.30pm, Monday through Saturday. I’d get one hour off for lunch and two for dinner. I’d not see, let alone answer, any mail, and would not go near the phone. No one would come to the house. Lorna, despite her own busy schedule, would for this period do my share of the cooking and housework. In this way, so we hoped, I’d not only complete more work quantitively, but reach a mental state in which my fictional world was more real to me than the actual one.
More here.