This is a very interesting question!
I actually just recently tried AV in my hair [on friday], and it worked wonderfully.
I am protein sensitive.
I used Aubrey organic's Aloe vera juice, put suave conditioner in my hand and drizzled a little of the juice, rubbed and worked it into my hair.
I then put SMU gel..
My hair , during the drying process, looked a little frizzy but once it was completely dry, my oh my! My curls were gorgeous. They looked not only defined but actually very healthy. =]It did seem to take away the wild volume I usually go for, but for the gorgeous healthy looking curls I got..doesn't seem to big of a drawback.
Point is, i didn't have dry straw-like feeling hair that I would usually have if using a protein product.