Hmmm, I'm not sure. I've used it as both a RO and a leave-in and have never noticed any build-up. I don't co-wash, but I low-poo with the Shea Moisture Coconut & Hibiscus shampoo and have never had issues.
I know some will disagree, as for quite a few here Shea Butter can build up. Just, in my experience, it's never been an issue
3B. Medium porosity. Medium Thickness. High density.
Low-poo: SM Coconut & Hibiscus
Conditioner: Jason Moisturising Aloe Vera
Leave-in: Aunt Jackie's Curls & Coils Quench Moisture Intensive OR a baptism rinse.
Gel: Ouidad Climate Control Heat & Humidity
Re-moisturising/refreshing: TRESemmé Naturals conditioner
UK curly. CG since October 2013.
Growing my hair out Rapunzel-style