Idea is for a new work type "Study" to the right of "Research" on the work grid. It's a way to improve skills when there is no work available to advance them. When Study becomes the active task, the colonist's work priorities are scanned and the highest priority work with a computed skill less than 5 becomes the focus of study. The underlying skills for that work increase through study, but not as quickly as they increase while actually performing that work. Once the average skill for that work is 5, the next work priority that can be improved through study becomes the focus.
There could then be Research tasks that allow for Advanced Study which could raise skills to a higher point. Perhaps 8 or 10.
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