Teehee, ain't it the truth! I only left mine on about 3 minutes, too, and noticed a difference. My hair's in pretty good condition, though, and I don't think very porous, so likely not starving for protein.
Former longhair, now CG, living in N. California where the fog meets the wind
3a/b, fine, normal porosity/elasticity, high density
Conditioner wash and style. That's it!