R1:18161d00a08d

Update some storage documentation for new adjustment workflows

Summary: Ref T1191. General update of this document, which remains mostly accurate. Remove a warning.

Test Plan: Read document.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T1191

Differential Revision: https://secure.phabricator.com/D10760