Natural hair & relaxed hair =? Same haircare

This weekend, one of my best soror friends came to visit.  She's relaxed, and I noticed that her hair had grown fairly significantly since I last saw her in May.  In May, she was shoulder length (SL), now she's a solid arm pit length (APL).  I asked her what she did to care for her hair and guess what her response was...CO-WASHING!!!!  She said that she co-washes 3 times a week and it helps keep her roller sets fresh :) AND it keeps her hair moisturized.

Another associate of mine grew her hair down to APL in 1 year through braids (with extensions) by co-washing her hair on a weekly basis.  She was natural underneath the braids, and stated that keeping her hair moisturized through co-washing is what helped her RETAIN length.

It's been said 1,000,000 times that black women "can't" grow our hair long, but if we need touch ups on a 4-8 week basis our hair CLEARLY GROWS, we just don't RETAIN any length.  Think about it: if every time a sista gets a touch-up, she has about 1" of new growth, but she gets a trim b/c her "ends are bad," and another 1"+ is cut off, and she's back to square one.

If relaxed heads adapted similar haircare techniques from naturals (Ex. co-washing, protective styles via bunning, sealing ends, using more natural products), would they see better retention and THUS more growth???  POSSIBILITY!!!