I don't have quite the same hair properties as you, but I will share my experiences with glycerin. I live in the Pacific Northwest and it is currently rainy and cold. I find that even if I use a deep conditioner as a leave in on my dry hair, I still cannot use anything with glycerin! If I do, it feels okay at first, but by the end of the day my hair is super dry and tangly. Yesterday it rained all day and I tried a new curl cream (mop-c curl defining cream) which I bought because it didn't have glycerin listed on the ingredients on the website. When I received it in the mail, glycerin is listed about halfway down in the ingredients. I was so bummed but decided to try it since it has such great reviews. My hair felt fine in the morning, but was soooooo dry by the end of the day. Aloe seems to be fine on my hair so I don't know yet if I have to avoid all other humectants or not. I also have found that I have to be careful about which proteins I use. My hair likes keratin best, although soy is ok as well. I also find that my hair tolerates it best if I only use it in a product I rinse out. I can't leave anything in my hair that has protein unless it's VERY far down on the ingredient list and I can't do that more than once a week. I usually low poo every 2 or 3 days so I suppose if I didn't use shampoo I might have to avoid it altogether. I love the new Evercurl Hydracharge leave in cream, but it has the a-cone in it and the fragrance is almost too strong for me. It is the only product in that line (other than the oil) that is glycerin free. I use it about once a week and always get good results.
3a, baby fine i/ii, low to normal porosity, protein sensitive
Mod CG since 5/12, from rainy Western WA
dislikes: glycerin, wheat protein
Likes: moisture, Mag Sulfate
Poo: Elucence Moisture Acidifying Shampoo
Cond: CJCR, DB pumpkin seed, TJ TTT, Elucence MB
Protein: one & only Argan oil hydrating mask
Style: UFD curly magic, Sweet Curls Elixers flax seed cream and HHG (Etsy)