For the project I am working on, this isn't the most directly useful book--though it will be an important reference point for part of the discussion.
In terms of Schnechner's project though, this book succeeds really well. This is a textbook for introducing the complicated concept of performance studies, which is a really broad discipline. Schnechner demonstrates how performance always vacilates between the theatrical and the everyday, in that we are always more or less performing with greater or lesser degrees of theatricality. Of course, then from a performance studies perspective one would need to actually define "theatricality," which Schnechner does through discussion of continuums, ranging between different kinds and degrees of performances.
I had actually forgotten--because I don't use traditional textbooks in my classes--how interesting a genre the textbook is (itself a written performance). Schnechner gives us tons of excerpts from the various people he makes reference to, some of whom are dramatists, some philosophers, some movie people, digital media specialists, performance artists, and so on. We get excerpts from their writings about performance theory, as well as highlighted keyword boxes defining specific important terms. Also, tons of photos. Again, the textbook is a fascinatingly distinct genre.