There are ingredients that you want to stay away from in those products because they are drying--the salts and the witch hazel. They might increase the tangles.
While low porosity hair can be healthy, not all healthy hair is low porosity. It's possible to have healthy hair of any porosity. I would think the stylist would comment on hair that long being healthy. When I was young, college age, I had waist length hair that was so dense, I couldn't put it in a single braid. It was just too thick (and my hair is fine.) It still didn't tangle. I've lost the density through age, thyroid and a medication I take.
You hair might not like protein because it's coarse. NC.com is the only place I've seen that low porosity hair might not like protein. Since your hair is so dry, that might contribute to the issues with protein.
You may want to consider buying bulk bases from companies like Essential Wholesale and Ingredients to Die For--you'll have to read the ingredients carefully because they do contain the proteins. The quality is significantly better then you'll find with drugstore and salon products. They don't use all of the chemicals. EW does use some witch hazel, but I don't remember if it's in the hair and/or skin products. I won't use it on either.
3a (Corkicelli), highlighted, fine, low porosity
modified CG, since April '07
CG since 3/11/08
HGs: Anything Sevi; Curly Kinks Satin Roots, Curlycue ReNew and Coil Jam; homemade FSG and okra gel; soap bars; UFD Curly Magic; Botanical Spirits Jellies, CJ Repair Me