I also have some strands, not many but a section on the crown, which have bumps and kinks when you run them between your fingers. I don't see that as a sign of high porosity though, because I can feel them whichever direction I'm running the fingers in, and also because if you hold those hairs to the light you can actually see kinks and 'diversions' in the strand. I am high porosity though, at least I think
I am, but my indicator for that is more a feeling of general resistance as you run your fingers against the grain, rather than kinks. Also the general behaviour of the hair - ie. if I leave a conditioner on a while, there can seem a lot less to rinse off than I put on, it dries out quick (it is colour damaged), and I cannot even imagine the beading thing.
The bumps you feel might be porosity related, just suggesting one way they might not be. Re. fine and coarse, I found this link quite helpful,
Curl Junkie - Natural Hair Care for all types of Curly Hair!: My 2 cents on Protein/Texture/Porosity/Moisture Balance! :-)
UK based wavy
Mostly waves, but curls and straight bits too!
Fine to medium, high porosity, medium density, very low elasticity
Highlights damage (growing it out), seems to like protein and need lots of moisture.
Cleanse - CJDF, trying out low poos ; Co wash- Uk chemist brands, Urtekram Rose or Aloe, Hairveda Amala Cream Rinse; RO - varies, Tigi Moisture Maniac, Desert Essence Coconut ; Leave in - Keracare natural textures; Sealant - argan oil
Trying out new things, still looking.