I prefer to merge these sections into the workflow sections, resulting in an outline like:

* Form workflow
    * 1) Pre-populating the form
        * A) The `PRE_SET_DATA` event
        * B) The `POST_SET_DATA` event
    * 2) Submitting a form
        * A) The `PRE_SUBMIT` event
        * B) The `SUBMIT` event
        * C) The `POST_SUBMIT` event