Here are some possibilities:
* "Daylight saving time": This is a seasonal adjustment to time, typically moving clocks forward in the spring and back in the fall to make better use of daylight hours.
* "Daylight robbery": This refers to an unfair or overpriced purchase, often implying that the buyer is being taken advantage of.
* "Daylight saving": This could be a creative way to say "saving money or time" during the day.
* "Daylight savings": This is a possible misspelling of "daylight saving time."
Without more context, it's difficult to determine the intended meaning of "daylight sanity."
Could you please provide more information about where you encountered this phrase? This will help me understand what it might refer to.