1) The document discusses how to customize views and menus in OpenERP Online (now known as Odoo) for an insurance expertise company in a sustainable way without custom modules.
2) It provides examples of adding fields, groups, menu items through inherited views to link customers, issues and meetings while ensuring the customizations can survive updates.
3) Specific customizations demonstrated include adding address/type fields to views, renaming menu items, adding selection/many2one/one2many fields and tabs to link related objects like customers and their issues.