Thanks for the feedback! The business with `cbind` is a facepalm, I'll definitely fix that. I don't think it will affect performance much since that last step w

Thanks for the feedback! The business with `cbind` is a facepalm, I'll definitely fix that. I don't think it will affect performance much since that last step won't be repeated many times, but it makes me cringe now knowing how redundant it is. Good advice on `col_grouping` as well, accessing those components of an aggregation rule by index rather than by name is a bad code smell and decreases readability for sure.