I wasn't attempting to connect porosity and protein. I asked only because many people don't know how to help their low-po hair accept moisture.

OP - to start repairing your hair, you might consider a light PT. This can even be just a protein rich conditioner. Your hair might be protein sensitive but still needs a little. Mine needs a protein-rich RO occasionally - any more than that, though, is way too much. Follow the PT with a good DT.
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
LI: KCKT or CJSL
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.