One of editing's occupational challenges is to learn and apply any number of different style guides when moving from one employer to the next, depending on particular house style preferences. There's AP, GPO, and Chicago style guides, to name just a few.
Being responsible for riding herd on style is a process of learning, unlearning, relearning, etc.
Take that challenge and increase it by an order of magnitude, and you've got the nearly impossible juggling act that me and my fellow copy editors (for the freelance, online content editing I do) are responsible for.
We currently have no less than sixteen sets of guidelines. These comprise: eleven categories of articles (how to, about, fact sheet, etc.); two blacklists (competitor websites never to be cited); and the house, image, and references guidelines. Plus, we must absorb and apply whatever information and/or feedback that our roughly 400 peers receive from our various team leaders or glean from looking at other forums on our website in addition to our own for copy editors.
Many of our forum posts reflect the sheer frustration of trying to sort out an incredible amount of information.
I'm hard pressed to recall any time since '83 (when I started my editing career) that so much effort has gone into so few words (the articles are from about 150 to 400 words). Much of that effort involves just preparing to edit.
To borrow a phrase from William Wordsworth, "The style guides are too much with us."