Bruce, I can sympathize. I just spent some time recently trying to understand Table/Cell Styles also.
It ended up that I only used the Table Style for the outer border of the entire table, and left the rest to Cell Styles.
The best method I found was to create Paragraph Styles and attach them to the Cell Styles, so that when I select a set of cells, both the Cell Style and Paragraph Style would apply.
It’s really important for [None] to be selected anytime the Cell Style should take on the Table Style. (or delete a point size so it appears blank).
Not sure if I help much, but you’re not alone….