Quote from "Delivery Manager Course 1: Building It right" "As a rule of thumb, extensions should be wrapped by eSpaces that will provide a more simple interface with external systems"
Please explain, the reason why it would be necessary for an extension to be wrapped by an eSpace before it can be consumed?
Example: You have an extension that consumes 3rd party web service X
Your Application Z would like to connect to service X, you can just reference the extension X and simply consume it, without first wrapping it around another eSpace, as suggested in the training material.
REF: http://www.outsystems.com/Training/Module.aspx?MaterialId=396&CourseId=3&ShowTest=False&SkillLevelVersionId=148&RoleId=155