I guess I am different. When I see 3C hair, I always take it to mean that you have a combination of 3B and 4A curls on your head. That is why I classify myself as 3C. I thought it was to bridge those curlies that had both curl sizes, hence the kinky curls. I have always felt it was redundant to say that I have 3C/4A hair. It is all one in the same.
The classification is just that. A reference point, not to perfectly place each head of hair. You begin here and then branch out to what your particular head of hair needs.
3C s-curls, coils, and corkscrews
TIGI MM, QB AOHC, KCCC, MJ CM, MJ BBC, JC WDT, CD HM, CD MHH, DC OneC, Veg Glyc, and Jojoba oil.