Leave Substituting for the Experts
Commercial bakers not only know which ingredients can be subbed for the other, but they also know how things work together. To become a professional baker, you need to take courses that teach you about food theory, food science, and more. This allows them to sub out one item for the other and get great results.
For home bakers, however, subbing out ingredients may take something vital away from the recipe that causes it to fail. Unless the recipe mentions that something is optional, such as nuts or a specific flavor chocolate chip, you should stick with the basics. Many recipes will also list substitution options, so you don’t have to guess about your own.