Actually, you do need to worry about the pH. The problem is that if your developer is slightly basic, you will lock in ferric oxalate to the paper fibers to the point you will never get it to adequately clear. A pH of 6 for your developer will make your life infinitely easier when you get to the clearing steps. The pH worry also is relevant for the commonly used water-only clearing step a lot of workers use right after development and before chemically assisted clearing. If your tap water is slightly basic (even pH 7.5) you will get permanent ferric locked into your paper. I speak from experience here.