I find every heuristic comparing preparation time to total work time unreliable.



Writing isn't always 10% inspiration and 90% perspiration. For me, it's often 90% milling around trying to maintain some semblance of self esteem while waiting for inspiration, 1/2 of 1 percent inspiration, and the other 9 1/2 percent mildly pleasing exercise. No sweat at all. Other times it's 100% just doing it. Still other times it's 110% not accomplishing anything at all.
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