I've had this happen often enough that when refactoring something tricky I like to copy the function and rework it. Then I'll change references from the old met

I've had this happen often enough that when refactoring something tricky I like to copy the function and rework it. Then I'll change references from the old method to the new one one at a time and test. One of my favorite methods returned a Map<Long, Map<Long, Map<Long, Map<Long, Long>>>> with no comment explaining what any of those Long values were...