Quotes from Carl Schroeder

The most obvious effect of inverting a chord is to change its bass note, and one result of voice leading through the use of inversions is the creation of melodic bass lines that connect from chord to chord by steps rather than by the wider leaps common when root position voicings alone are used.

complexity doesn't exist for its own sake, or to prove a theoretical point, but because it provides the right sound at the right time to express very human emotions.

Only by analyzing the melody to locate the tonic can a key signature be identified as major or minor.

To the eye, the key signatures of relative keys are identical. Minor key signatures are laid out on the staff just like major key signatures. The sharps and flats are in the same octave and same order. Only by analyzing the melody to locate the tonic can a key signature be visually identified as major or minor.