Your diagram states, ‘Managers and model objects together form “The Model.”‘ Model are data objects and not really where you would be performing business logic. The only purpose of the model object to to feed data to the Presentation Model, which renders the data in the view.

Business logic is best handled in the Managers.

It is apparent to me that you do not have a full appreciation of how Mate is to be used. A good way to master using Mate is to build, run, observe operations, and understand most of the Mate examples found here: http://mate.asfusion.com/page/examples