 The problem of avoiding "irregularity" is most evident in spelling, where internal sandhi is not transcribed, because there is the idea that morphemes should be immutable.For example, the "correct" spelling is "syönpä" ("I eat" with emphasis), even though the pronunciation is usually "syömpä".The explanation is that "-n-" and "-pä" are in different morphemes just like the explanation that English "boys" is not spelled with a "z" is that they are in different morphemes.