Don't let tactical diligence overshadow strategic laziness. Do not repeat at a low level. Any task can be divided into two parts, the relatively easy part and the relatively difficult part. A reasonable schedule should be like this: Do the easy parts quickly, and put the time saved on the difficult parts. Don't waste a lot of time on the simplest things, spend 20% of your time solving easy problems, and spend 80% of your time thinking and researching difficult problems. Rather slow at a high level than repeat at a low level.
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