It was adnam's recognition that made me think it was used before. Also voidnull appears to have a long standing interest in this concept, and so might have use

It was adnam's recognition that made me think it was used before. Also voidnull appears to have a long standing interest in this concept, and so might have used a variant of it before. Again, just a data-point -- the idea is to sort a giant list, not necessarily filter it.