On the other hand, Sue Becker from Bread Beckers does not think that soaking is necessary. She claims that our small intestine produces enough phytase to properly digest the grains. She refutes claims that grains have always been processed this way.
I couldn't fully choose a "side" just based on my research. (Well, limited research. I'm not claiming that I've researched anything to the fullest). I have an issue with Sue's approach because she is promoting a biblical view of bread but rejects the importance of natural leavening, which is how bread was made in those times. On the other hand, I wasn't convinced that all grain products were carefully soaked in traditional diets, or that it is entirely necessary.
So I did a highly unscientific experiment. I haven't developed the skill of making bread, but I do like to make a lot of whole grain quick breads (muffins, pancakes, scones). So I decided to try both methods; sometimes I soaked my flour, sometimes I didn't, and I paid attention to how I felt after eating two or three freshly made items. I noticed that when I ate the unsoaked versions, my stomach felt a bit unsettled for the next few hours. When I ate the soaked versions, I felt fine.
Therefore, I decided to soak grains before eating as much as possible. I don't feel there's a need to be religious about it, as I'm not convinced that unsoaked grains are indigestible or very harmful.
I also prefer the texture of the final product when soaked. My freshly ground flours end up a bit coarse, and the final products can be grainy and heavy tasting. But when soaked, pancakes and muffins are softer and have a pleasantly mild taste.
Soaking is a simple process. Mix together whole grain with a sour liquid; my favorite is buttermilk but you can also use yogurt, kefir, just make sure your choice has live bacteria (Lactobacillus). Raw apple cider vinegar or lemon juice mixed with water can also be used, although the dairy options will give a better flavor and texture. Let the mixture sit at room temperature (cover with a towel or loosely with a lid) for 12 to 24 hours, then add the remaining ingredients and prepare.
A good first thing to try is pancakes. Many soaked recipes can be found online to try. Nourishing Traditions has instructions and a lot of recipes for soaking grains. This article also looks like a good summary.
Links
Weston A PriceBread Beckers
Nourishing Traditions (Amazon)
The Nourishing Home
Kitchen Stewardship