A possible exercise?
A long time ago there was mention of a speed-building practice in a thread on the blog: http://gregg-shorthand.com/2008/12/19/methods-of-attacking-shorthand-speed/ (Note: Link to the _Factors of Shorthand Speed_ document now kaputt!) The idea was practicing for a long time without breaks to force the fatiguing muscles to learn how do the work with minimal effort. I am…