The initial impetus for this inquiry came from a question posed by Arthur Mendel during a coffee break in a Bach seminar some thirty years ago. Why, he asked, did Bach notate the last movement of the fifth Brandenburg Concerto in two-four time, with triplets rather than in six-eight time?...
"Bach's Tempo Ordinario: A Plaine and Easie Introduction to the System,"
Performance Practice Review:
1, Article 5.
Available at: http://scholarship.claremont.edu/ppr/vol13/iss1/5