Context: Some clock-shift problems could be avoided by adjusting clocks continuously or at least more gradually—for example, Willett at first suggested weekly 20-minute transitions—but this would add complexity and has never been implemented.

Question: Willett's first suggestion was to change clocks by 20 minutes how often?
Answer: weekly

Question: What drawback would changing clocks gradually add to the process?
Answer: complexity

Question: What could be avoided by changing clocks more gradually more often?
Answer: Some clock-shift problems