Initiative in an SOA architecture

I am charmed of the figure below (originally by BEA). Most of the layered SOA models put the GUI layer on top, near the user. Then follows the proceslayer, business logic layer and data layer.

I always wondered which layer had the initiative. It always seemed that initiative coming from the user had to come from the GUI layer and had to pass all layers.

In this figure however it seems (if the user is on top of the figure) that this composite applications layer wil have the initiative. Only after some action in that layer, the user will get a presentation. Presentation is not first. This seems a logical order to me. The Composite Applications layer also can access all other layers, without going through the others. That is the second thing I like. I am still wondering whether accessing Information Services directly is a wise thing to do, without going through Business logic. I can imagine that is ok when just accessing and viewing information.

How to make your enterprise a service oriented enterprise?

I was pointed at the contribution of Niels Klinkenberg to LAC 2005 with respect to SOE (Service Oriented Enterprise). The relation is made between service orientation to a network of organizaties, aimed at optimal flow. It states the conditions of success to install a SOE and make it work.