Does the iconostasis perform a similar function to the rood screen? (Except that the congregation can see through the rood screen and into the holy of holies - this is probably not the right term, but I can't think of the correct one.)
What is the effect of the creation of a "holy of holies" - both theologically and in the functioning of the ritual / liturgical space? Since the iconostasis is opaque and the rood-screen is permeable, how does this affect the congregation's view of the mystery being enacted by the priest? Is there a theological basis for this difference in the design of the Orthodox and Catholic church buildings? Does physically seeing the holy of holies, or any other visible symbol of the mysteries, make it more or less visible to the inner eye of the heart?
As a point of comparison, Roman temples also had an inner sanctum, which was in the centre of the temple rather than at the end (I wonder how this affected the lay person's perception of their connection to the divine?) This inner sanctum was under the cella and surrounded by the ambulatory.
According to Wikipedia, as well as being the inner sanctum of a temple, "In early Christian and Byzantine architecture, the cella is an area at the centre of the church reserved for performing the liturgy." Interesting because the cella was at the centre of these early churches, and therefore it sounds as if the layout was borrowed from Pagan temples.
A quick Google suggests that the introduction of an "opaque" iconostasis is a relatively recent innovation, but that both the iconostasis and the rood screen were intended to demarcate the area where the mystery was performed, and indicate that only the ordained could enact it. I observed a similar (albeit vestigial) manifestation of this idea in a Hindu temple I visited, in the form of a rail in front of the main shrine; only the priest could go behind this rail.
However, the cella in Egyptian temples was apparently totally hidden from view, so the idea of the mysteries being completely hidden from the laity is clearly not new.