Diego Collado's Grammar of the Japanese Language
One doubt that remains in assessing Collado's use of Rodriguez' material is that perhaps his presentation of the most readily understandable material in the Arte is not so much an effort on his part to simplify the learning of Japanese for his students, as it is a reflection of his lack of adequate familiarity with the language he was teaching.
The Phonological System
A study of the phonological data reveals the Ars Grammaticae Iaponicae Linguae to be of minimal historical value. Any student of the phonology of early modern Japanese should turn to the far more reliable work of Father Rodriguez. Nevertheless, certain aspects of Collado's transc