For PEX 2.0's documentation, it is important to have a consistent style so that the documentation is easy to follow for users.
A tutorial is a recipe for a specific configuration. It doesn't necessarily describe every aspect of a PEX feature. The goal of a tutorial is to provide a path a user can easily follow to achieve a certain goal, like setting up an admin group or setting up a ladder of membership levels.
Each tutorial should follow a step structure, where each step describes what is being done, as well as how to do it in the various interfaces to access PEX (commands, gui, potentialy text file).
A subsystem description describes how a particular component of PEX works in detail. It's not focused on a specific way of doing things, but should give the information necessary to use the full feature set of the subsystem. Sections of one of these pages might be:
Effect on a subject of the various configuration states
How to apply these changes directly to a backend (file?)