Take it with a grain of salt, but I think the grabby vs. slippery is not so much porosity, but it's about TEXTURE. A lot of wavies, especially ones that easily get weighed down, need something that is more texturizing than detangling. Slip is just that.. it slicks the cuticle to reduce friction and the hairs slide over each other easily. Texturizing does the opposite. That's why when you go to the beach you get really cool beachy waves and lots of volume, but your hair "feels" different, the salt in the water gives texture to the hair.
I like it right in the middle. A moderate amount of slip. For every day or for a leave-in anyway.
Lady Crispina, Confector of Pharmaceutria and Conjurer of Exquisitus JuJu, in the Order of the Curly Crusaders