Well, I'm not known for mainstream advice lol, but for whatever it might be worth: I think Ms. Lorraine Massey has the right idea about some things, like how regularly using sulfate-based shampoos can be curl-killing.
But I have found some of her methods to be a bit extreme. Like how she used to say any blow drying at all is bad - she called it "blow frying" (but she did go take that back just in time to release her own blow dryer/diffuser set). Or how she doesn't think curly hair can be properly cut wet (it can).
I don't agree that shampoo should never be used. I think it's actually a terrific idea to wash curly hair every once in a while with straight-up sulfate shampoo (a clarifier, more specifically). Sulfate has a wonderful way of removing build-up and will not compromise the integrity of the hair at all when done once in a while. Plus, it's simple, it's cheap and it doesn't have a weird consistency like baking soda, and it doesn't attract bugs the way brown sugar can (plus brown sugar also has a weird consistency). Plus, the two aforementioned items won't necessarily take away all the buildup, and aren't necessarily less drying than a sulfate shampoo. It took personally suffering a really bad case of build-up to adjust my philosophy concerning this.