I am all for anything that makes the user feel that it's working, but I did stumble upon this blog post by the Beauty Brains a few days ago and thought it was an interesting look at amino acids:

3a and strictly CG since August 2007. Porous and on the fine side. No to magnesium sulfate and glycerin. Yes to protein! Favorites:
CO-WASHES: Suave Coconut
CONDITIONERS and LEAVE-INS: Mop Top Daily Conditioner, KBB Nectar, Aubrey GPB or Island Naturals, Robert Craig, Any Jessicurl
GELS: Fuzzy Duck, B5 Design, MGA Scultping, BRHG

Fotki password: chuckle
Blog: http://jillipoo.blogspot.com/
Twitter: nopoojillipoo