Not testing the PH is fine for living soil, BUT you can run into problems as I did last year. I was convinced to use something I had never used in my soils, this upset the balance and my PH dropped. I did not have anything to test PH with, the probe I had was dead. When I got the new equipment, I tested my soil to find it had crashed to 4.0, no wonder the poor girls looked sad.
BTW it was perlite that I added that caused my PH to crash, when combined with the powdered sulfur (and water) I was using, the outcome was a large production of sulfuric acid.
Until one can get a handle on living soil, and the issues that can come into play, I still say PH it!