Although literary culture in Japan was at a high level over 1000 years ago (the first novel was written there in the 11th century, writers, poets and artists were held in high regard and historical and genealogic records have been preserved), some modern Japanese may regard parts of the histories as myth, much as we are skeptical of much of our more fragmentary western writings of that period.

I wonder that this may have contributed to historical data from that period being dismissed by modern engineers.