I'm reminded of the saying "Make things as simple as possible but not simpler". In other words, you may have assumed too simple of an answer.
An accepted hierarchy for the animal kingdom is as follows: kingdom, phylum, class, order, family, genus, species
There's one problem with it. Biologists have already created spreadsheets with "super class" and "sub class" columns to handle new generalizations in-between the levels of an accepted hierarchy. But, their software won't allow them to enter their new data.
By going "backwards" in intelligence from a relative solution to an absolute solution, and backwards from complex to simple, you have gone from a general solution to a specific solution. If you must have performance, then it was a good choice but the price will be paid in maintenance.
I don't have a problem with loopy code which generally outperforms CTEs in depths over four.