Subsequent to the publication of the analysis in the The  Esoteric Keyboard Temperaments of J.S. Bach, several comma-based variants appeared in a popular humanities journal. Authors included Bradley Lehman, David Ponsford, Daniel Jencka, Richard Maunder, Carl Sloan, Kenneth Mobbs & Alexander Mackensie and Stuart Isacoff. The proposals differed in terms of assumed starting note, assumed comma fractions and assumed direction for reading the spiral. Hundreds of such alternatives exist, however judicious selection according to historical precedent yields a subset of historically informed variants. Further selection can be made on aesthetic grounds. Such a methodology predicates conformity with the historical record and pleasing aesthetics, but lacks the scientific aspect of testable consequences from assumed a priori hypotheses. Moreover, none of the alternatives have satisfactorily accounted for the two differing end points of the spiral.

The proposal by Lehman and Jencka is perhaps the most outlandish, being derived from a startling assumption that the cover page is read upside down as follows: 

Both authors, moreover, assume that the c-serif attached to the letter 'C' of 'Clavier acts as a pitch reference to indicate the note 'C' and that in consequence the tuning starts from 'C'. The pitch reference assumed by Jencka and Lehman is illustrated below:

Two objections to this proposal are:

  • The 'c' is upside down in the assumed reading, so  the alleged pitch reference is of little benefit. In the correct orientation, however, this would make more sense.
  • One 'c'-serif is prioritised, while the other equally prominent 'C'-serif attached to the 'D' of 'Das' is ignored.
  • It cannot be reasonably assumed that the 'c' acts as a pitch reference as numerous similar examples of a 'c' serif occur in Bach-related handwriting and are obviously not pitch references. Such Illustrations, which would have given the reader a more balanced view, are notably missing in the Lehman paper.  To remedy this situation, some examples from Bach cover sheets are shown below:

BWV 1006

BWV 224

BWV 1004   

BWV 124 

BWV 109 

BWV 25 

Des Wohltemperirten Claviers 
Zweiter Teil (hand writing of Johann Christoph Altnikols)

BWV40

BWV45

BWV127