Well, for example, my hair is low-porosity. This means it does not readily accept conditioner. It means products often just sit on top of the hair and never absorb (e.g. Oil). so, i utilize heat to open the cuticles and get the moisture in. Most advice is to avoid heat - I now know that is advice I am better off ignoring.

As far as protein - my hair will sometimes respond well initially o products with protein. After a week or two at the most, it will suddenly be dry and straw-like. I also cannot go completely protein-free, so I now know to watch my hair and adjust the protein and moisture accordingly. (I'm still learning this part.)

I have been no-poo for over a year and only in the last month or so has it finally started coming together for me and it was only after I learned my hair properties. It completely dictates what products work best for me. My hair may not do everything low-porosity hair can be known for, or respond exactly how another's low-po hair might, so it still isn't a precise formula. but it sure narrows down the field of products and techniques to try!
remember, with all advice or suggestions for your hair, YMMV!!
My hair:
2b wavy, medium texture, low porosity, med-high density. Protein finicky.
My routine:
Cleansing: DCNP, every 4-5 days (occasionally use CJ cleansers).
RO: CJSC, occasionally use JCDC
Gel: KCCC, CJCIAB for 2nd day hair (sometimes third)

Heat is my friend: warm water rinses, steam caps, and diffuse dry. I love CLU cloths and my Denman.