How Chart Rules Handle Edge Cases Fairly
Launch library · evergreen read

Edge cases, such as a collaboration between artists from two genuinely different genres or a release available in several noticeably different versions, test a chart's rules far more thoroughly than the ordinary, straightforward releases that make up the great bulk of everyday chart activity week to week, year after year without fail.
Well designed methodology anticipates at least some of these edge cases in advance, laying out clear rules for handling them before an actual dispute ever arises, rather than scrambling to invent a fair sounding rule only after the fact under real, immediate pressure with everyone watching closely.
How a chart handles its genuinely difficult edge cases, rather than its easy, routine ones, is usually the clearest and most honest indicator of how seriously that particular chart actually takes its own stated methodology, and, by clear extension, its own long term credibility with careful readers over many, many passing years and seasons.