Historical clue formulations

• Sharpen — 2026-06-27
• Sharpen — 2026-06-02
• Sharpen — 2026-01-11
• Sharpen — 2025-11-02
• Perfect — 2025-10-09
• Refine, as a skill — 2025-09-22
• Smooth with a whetstone — 2025-07-13
• Sharpen, as skills — 2025-06-17
• Sharpen — 2025-04-29
• Perfect over time — 2025-01-04
• Refine — 2024-06-26
• Perfect — 2023-07-06
• Perfect — 2023-03-03
• Give an edge to — 2023-02-03
• Sharpen — 2022-12-13
• Sharpen, as a knife — 2022-07-19
• Sharpen — 2022-01-18
• Refine, as a skill — 2021-12-14
• Refine — 2021-12-12
• Sharpen — 2021-09-19
• Perfect, as skills — 2021-07-20
• Put an edge on — 2021-05-05
• Sharpen — 2021-02-15
• Give an edge — 2021-02-06
• Sharpen — 2020-08-10
• Sharpen, as skills — 2019-12-30
• Improve gradually, say — 2019-07-14
• Put an edge on — 2019-02-10
• Perfect — 2019-02-08
• Sharpen, as one's skills — 2019-01-30
• Practice to improve — 2018-04-11
• Perfect — 2017-11-18
• Fine-tune — 2017-11-02
• Sharpen, as a skill — 2017-09-12
• Sharpen, as skills — 2017-01-16
• Get an edge on — 2015-05-08
• Practice — 2014-02-05
• Sharpen — 2014-01-16
• Perfect — 2013-09-15
• Refine — 2013-08-01
• Sharpen — 2013-05-27
• Sharpen — 2012-12-04
• Practice, as skills — 2012-09-30
• You might rub a knife across it — 2012-01-29
• Make more efficient — 2011-09-24
• Aid in gaining an edge — 2011-08-26
• Fine-tune — 2010-10-13
• Sharpen, as a knife — 2010-07-05
• Opposite of dull — 2009-10-23
• Sharpen — 2009-09-16