I am currently doing some work through Kendall Briggs' The Language and Materials of Music. For context, I graduated years ago and am working through his book as a brush up on things I have forgotten. The reason for picking his textbook is I heard great reviews of it.
I'm currently going through first inversion part writing. In this, he says to write a soprano note by exchanging when the bass has the root or the third. If the bass has the root give the soprano the third and vice versa. The exception is when you have two consecutive root position chords. Then you follow the Law of the Shortest Way (smoothest part writing).
My issue is that as I go through this, it doesn't seem like very smooth part writing. There are large leaps of a sixth in the soprano, later followed by leaps of fourths or fifths in the alto and tenor lines. I understand that isn't necessarily bad, but it is certainly different from what I had learned before with trying to keep lines smooth. With that, in some of his examples he doesn't follow this rule. He instead opts for doubling the third in a first inversion chord and then the fifth in a root position chord. I cannot see why he broke his own rule and so cannot tell when I should do the same. Lastly, he instructs you to write horizontally and not vertically. He asks that you write the entire soprano line, then entire alto, then tenor. This is fine, except when I find that something I did in the alto line (because I am following smoothest voice leading and the rule of switching the root and third in the soprano) creates an issue with the tenor line. I then have to redo the entire alto line from there, and then the tenor line.
Have any of you worked with this idea for writing a soprano line with first inversion triads? What are your thoughts on this?