Consider a test patch. I just spot treated with Joico to see if it would make my hair hard and brittle. Seems to be fine even without the DT follow up. When I get around to a fuller treatment, I will only apply to my damaged areas though just to be safe.
High Density, High Porosity, Medium Texture, 3B with some kink

Lo-Poo: No Preference
Co-wash: CJ Smoothing Conditioner
RO: CJ Strengthening Conditioner - HG
LI: CK Satin Roots
Styler: CK Coil Jam
Other Likes: Castor Oil; CK Twist Whip, MD CSC
Dislikes: Wheat Protein; Aloe LIs or Stylers