Myth #6) The fan shape, in which everyone can see the assembly and be close to the altar, is the most appropriate form for expressing the full, active, and conscious participation of the body of Christ.
This myth comes out of the questionable view that the assembly is the primary symbol of the church. The fan shape is a wonderful shape for theater, for lectures, even for representative government—it is not an appropriate shape for the Liturgy. Ironically, the goal often stated for the fan shape is to get more participation from the faithful, yet the semicircular shape is derived from a room for entertainment.
The fan does not derive from the writings of Vatican II; it derives from the Greek or Roman theater. Up until recently, it was never used as a model for Catholic churches. In fact, the first theater churches were nineteenth century Protestant auditoriums designed to focus on the preacher.
Professor of Architecture at the University of Notre Dame School of Architecture and founding editor of the Sacred Architecture Journal. His work continues the tradition of classical and Palladian architecture, also known as New Classical Architecture.—Wikipedia