I don't do anything special either. I wash/DC once a week & throw it back under a wig until the following wash week. Under my wig my hair is in celie plaits. That's it.
I think its just you. What I mean by that is every head of hair is different. Personally, I don't care if it guaranteed my hair would grow to my toes, Im not gonna go 4 weeks w/o washing my hair.
However, I do agree that ps is the way to go as the hair gets longer. Im getting to a point where I am ps more and laying off the heat.