If you haven't found the link, here it is Live Curly Live Free - Curly Hair Basics The float test is notoriously unreliable. The best way to determine porosity is sliding fingers from tip to root. If it slides smoothly, and possibly squeaks, it's low porosity. If there are bumps, depending how many, it's normal to high porosity.
My fine/low porosity hair never met a protein it didn't like. I do at least on PT a week and use a lot of products with protein.