These were tuning methods aiming at equal temperament, without benefit 
of the correct math for setting the temperament. Most of these tunings have each note 
within 1 cent of "correct" equal temperament, and hence most of them would pass the 
strict PTG Tuning Examination. On hearing the piano played, it is unlikely that even a 
discriminating ear would be able to distinguish any of these tunings from perfect ET.