I have been studying cookbooks and doing some recipe testing here and there, and I can tell you that not all cookbooks are put through a rigorous testing process. Baking is extraordinarily finicky, and any recipe intended for the home cook should be tested (in my humble opinion) not only in a home kitchen, but also by another home cook (preferably three). There are always instructions that can use clarifying, steps that seem obvious to the person writing it but not to the tester/reader, and visual and sound cues to doneness that can be gleaned from a fresh pair of eyes and hands testing a recipe. this process will also catch typos and errors before they go to print, but I imagine some are unavoidable.
I agree with Matthew that most of the problems stem from improperly scaling down commercial kitchen recipes for home use, and writing recipes for volume measurements and not weight measurements. In the Cake Bible, Rose actually pays such careful attention to scale, that she adjusts the quantity of leavening/baking powder for different size pans (look at the wedding cake / Rose factor section in the back). She is the first cookbook author I have seen that does this (though there are probably others). Every measurement in Rose’s books is provided in imperial and metric measurements, by both weight and volume (LOVE).
Some publishers and editors think that home cooks want only imperial volume measurements (cups) and will be intimidated by volume measurements. This is bunk. At a minimum, I agree with Matthew that weight equivalents should be provided (the people who are freaked out can just look at the volume column ). However, wonderful cooking teachers and cookbook authors (Julia Child!) are fine publishing recipes with just volume measurements: for example, Martha Stewart’s wedding cake recipes only have volume measurements, and I am sure they measure by weight in her bakery/test kitchen! I know it can be done by volume, but why would you want to make an entire wedding cake like this? At a minimum, I think the volume measuring method should be identified right on the ingredient line in recipes - i.e. spoon and sweep, or dip and sweep.
Ironically, the volume-only recipes probably make it MORE difficult for a novice baker to make the recipes successfully, which in turn probably hurts cookbook publishing. At a booksigning event for some bakers I met recently, they said their editor had pushed them against including weights, and they asked us to email them requests for including weights in their next book to show their editor!
When I find someone who writes reliable recipes, like Rose, Flo Braker, and others, I am really loyal and don’t venture too far from them. And when I find a recipe that clearly hasn’t been tested and causes me to waste time and ingredients, I tend to veer away from their recipes in the future (Ina Garten, Nigella Lawson*). I need to be more open-minded, though, and am going to buy Shirley Corriher’s BakeWise and Cindy Mushet’s The Art and Soul of Baking.
*I like these cooks, but not for their baking recipes. More for savory foods or other recipes that don’t require the same precision (i.e. Ina’s granola).