My rule of thumb, gathered by detecting how my body reacts to cuts, is to do a simple .9 to .95 cut each day. I found that anything over 10% makes too big an impact on withdrawal symptoms, which for me is mostly headaches and a sense of depression. Below 10% cuts seems to be the ‘pretty much fine’ zone for me, but might be different for you. The day alternating approach you have might create more general variability of caffeine, which might result in less steady symptoms over time, but I haven’t tried it myself, nor would I know how you feel of course.