I measured my hair, most parts are about 15" root to tip. So I intend to try this general regimen until the end of the year. If I can retain at least 1.5" in the 4+ months from when I started to the end of the year, I'll consider it a success.
Not quite 2 months later, most of my hair is 16" from root to tip. So, so far so good. I've been having more breakage than usual. I was thinking maybe I need a protein treatment. But then I remembered that I used to use coconut oil and didn't have this problem, even with barely ever doing a protein treatment. Coconut oil is strengthening, right? I'm going to go back to using it. I had switched for no real reason, to use up a bottle of another oil mix, primarily castor, that I had. I was enjoying castor oil, my hair was feeling soft and it was helping with the tangles. But I'm going back to using coconut oil at least half the time.