Hi Anne Marie,

I would describe letter, word, and glyph scaling parameters as things the paragraph composer can fuzzy-logic work with. Fuzzy logic typesetting has degrees of variability in it. The variability is constrained by the type designer's setting the minimum and maximum and desired values.

OTOH, tracking would tend to trump or over-ride the what-if-ing that the Paragraph Composer tries to do. And tracking values are more a one-size-fits-all uniformity.

.... or so it seems to me.

Mike Witherell