Scientists create models of the physical world, usually to predict or understand the behavior of physical systems. These models are implicitly judged by a variety of criteria, such as simplicity, accuracy, ease of use, suitability for a particular task, etc. And, as we all know now, things like fashionability and political acceptability also come into play. But, primarily, the model must agree with the physical situation observed in the real world. In science, models are not necessarily exclusive.
Different circumstances dictate different methods.
For example, sometimes it is more convenient to describe matter as waves, while at other times a particle description is preferred. Similarly, there are many possible frameworks in which to view Zen. Different frameworks suit different people at different times, and looking at something from several different angles can often give a clearer picture of it. One perfectly acceptable way to view Zen is simply as a physiological training system. The empirical core of Zen is zazen, or sitting meditation.