Pfaw! I make a sort of plosive sound of derision at that `too much' notion. I've run short of good Snughorn to read, it appears (Slughorn and Snape, and there isn't much of it about, wah) so for some reason, let's say writing practice, I feel compelled to compile a probably-not-at-all-comprehensive list of ( Theories found in fanfiction about Severus Snape's hair: )
61% Affectionate, 36% Excitable, 62% Hungry [also, 99% higher than others my age and `gender' (out of the two offered as options) in Affection, Excitability, Hunger _and_ Felinity! yow!]