Comment by vitaly-pavlenko

They are actually similar by circle of thirds. They go as 1-3-5-7-2-4 over the rainbow.

This makes main triads be smooth gradients instead of random three-color flags.

1 and 5 pitches are neutral because:

- they are neutral (a hollow tonic power chord)

- they don't convey any information about the scale. they only give a reference point to measure everything else against