I sometimes get this same issue - I sleep with my hair in a pineapple but will still sometimes get tangles underneath at the nape of my neck. I think this is because I do not have a satin/silk sleep bonnet or pillow case, and the hairs that rub on my pillow while I sleep are tangling up. Since I haven't gotten around to getting a sleep bonnet or better pillow case, I have found that putting some LI on my hair before bed helps. I also agree with waterlily that some of the issue could be the amount of protein in your routine. I also would not detangle dry hair - that will just cause breakage. If you need to detangle a specific section, I would wet it down and add some conditioner (like KCKT, or my favorite is As I Am LI) then detangle.
2c/3a, botticelli/wavy/'swavy (huh?)
fine, dense, normal porosity/elasticity, dry climate

My favorite brands are Kinky Curly, As I am, Curly Kinks, Curl Junkie, and Darcy's Botanicals. Also love sealing with oils (loving argan oil right now) and styling with jelly products (KCCC is my current favorite). Mostly trying to keep it simple!

CG since 12/29/2011