Natürlich unterteilt sie in Temperatur, das zweifel ich ja auch gar nicht an- aber eben auch in Klarheit. Wie du schon zitiert hast, sind alle Winter- und Frühlingsfarben klar, und das schreibt sie auch (Color me beautiful):
Winter: "You are best in clear colors and sharp contrasts. A Winter strives to stay snappy and should never wear muted, powdered tones."
Spring: "Your colors are the hardest to find, because they must be clear, never muted, and not too dark."
Während bei Sommer und Herbst die Temperatur am wichtigsten ist, was man daran sieht, was sie auf keinen Fall tragen sollten:
Summer: "All Summers should avoid black, pure white, yellow-beige, gold, orange, yellow-greens and all yellow undertones."
Autumn: "All Autumns should avoid black, pink, navy, gray, blue-reds and all colors with blue undertones."
Carole Jackson hat sich dafür entschieden, nach warmen und kühlen Farben das Buch zu strukturieren (vielleicht weil es für viele Menschen einfacher ist, die Temperatur als die Klarheit zu erkennen?), aber sie unterscheidet genauso in Klarheit.
Und in Color for Men:
"[...]The comparison table at the beginning of the charts shows some basic differences among the four seasonal palettes. First look at the different shades and tones.[...] The reds for both Winter and Summer are blue-reds, because they are cool (blue-based) seasons; the reds for the warm (yellow-based) Autumn and Spring are orange-reds.
Now examine the comparison chart for color intensity. Even though Winter and Summer are both cool, the intensity of their colors differs considerably. Summer's colors may be either clear or powdered (muted), while Winter's are all bold and intense.[...] Autumn has strong colors, either vivid or muted, but Spring has only clear colors. Spring's palette can be bright or light, btu never muted or extremely dark."