To put some hard numbers to the D65 vs C situation...
My Valspar flat enamel tinted Bermuda Beige. This is a pinkish-peach color to the eye.
"D65" L*a*b* values: 84.28, 6.36, 8.79
"C" L*a*b* values: 84.35, 5.82, 8.84
My Behr 1850 tinted Reference Gray (a very neutral dark gray).
"D65" L*a*b* values: 76.56, 0.01, 0.18
"C" L*a*b* values: 76.56, 0.05, 0.09
