Dave,
After posting the above reply, I decided out of curiosity to run a small test in which I weighed what I believed to be 8 oz. of flour and 1 cup of water on both my analog scale (a Polder spring loaded analog scale with manual tare adjustment) and my Soehnle digital scale (with electronic tare adjustment). I made four separate readings of the flour and water. For the water, I used a one-cup Pyrex glass measuring cup, which I filled to the one-cup level by eyeball and read on a flat surface at eye level.
The four 8 oz. flour "readings" on the analog scale weighed 7.60 oz., 8.75 oz., 7.75 oz., and 7.25 oz. when read on the digital scale. The four 1 cup water "readings" on the analolg scale weighed 7.2 oz., 7.2 oz., 7.5 oz., and 7.5 oz. The corresponding digital readings were 7.75 oz., 7.85 oz., 7.85 oz. and 7.55 oz., respectively. As you can see, even for relatively small quantities of ingredients, the swings can be fairly substantial. (Big Dave at PMQ also notes: "When you are doing extremely small batches, the slightest tweak in ingredients will have major ramifications in the end product. Small batches are un-forgiving".)
None of this is to suggest that you can't make a decent pizza dough without a digital scale and very accurate measurements. It just means that you will in most cases have to make adjustments to the flour and water. Even with a digital scale and accurate measurements you will from time to time have to make the same kinds of adjustments. I do exactly as Randy suggests in a previous post, and note what changes were required so that I can recalculate the ingredient amounts for future reference. The overall accuracy can also be improved somewhat by being sure to use measuring cups intended to measure dry ingredients (e.g., flour) to measure dry ingredients and to use measuring cups intended to measure wet ingredients (e.g., water) to measure wet ingredients. I sometimes see people use Pyrex glass measuring cups to measure both wet and dry ingredients. Doing this will throw off the accuracy of the measurements.
I'm a firm believer in accurately weighing ingredients like flour and water, and I consider my digital scale to be one of my most valuable pizza-making tools. As readers of my posted recipes may have noted, I usually convert my recipe ingredients from weight to volume measurements. This is done only to benefit those who do not have any scale, analog or digital. So, the volume measurements shouldn't be taken as absolute gospel. They are approximations only and may produce results that vary (hopefully not too much) from those produced using the more accurate and precise weight measurements.
Peter