What about the 3rd option, getting two tasks done?
- Grind for 1 hour and assuming 90% success rate, finish the task 9 out of 10 times
- Sleep
- Finish another task in 15 min with, again based on your assumption, a success rate of 100%
In start-ups there is usually a near endless list of tasks to solve so this would be the most productive approach. Again, based on a lot of assumptions.
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