That's a good lesson, pghboemike, very thorough.
I feel if the teacher is compelled to instruct in basic chord and scale theory in the middle of a class on inversions, he is teaching pre-requisites. Shouldn't have to, on guitar, that is.
If a person understands the theory first, all he should need is the idea of what inverted chords are, and an example, such as the Cmaj chord in the first, third, fourth, and sixth positions on the neck; that is, 5-1-3, 1,3,5, 3,5,1, and 5,1,3 again
at 12th fret, position six, and he or she should be able to take it from there.
You are absolutely right, pghboemike, in stressing triads -- that's the direct route for learning the neck, and playing in all keys.

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