I've mentioned before that I really enjoyed the first Pirates of the Caribbean movie. Much more than I liked any of the later three movies, though each of them had their own individual moments which were enjoyable. Part of that may have been the fact that it was unexpectedly entertaining. Come on, a movie based on a theme park ride? It sounded like a disaster waiting to happen.
But I also think that one thing that was present in large doses in the first movie and got kind of lost in the later movies was a sense of fun and whimsy. The first one never really felt too serious, the latter ones did and their attempts at being fun sometimes felt forced in a way that the first movie's humor rarely did.
I'm not really looking to talk about fun in stories today, though that certainly would be a good topic. But I was thinking about guidelines and that word makes me think of Geoffrey Rush's character Barbossa bantering with Keira Knightley's Elizabeth Swann. At one point, she appeals to his honor as a pirate and the rules of the Pirate Code. But Barbossa points out that not only is she not a pirate and therefore not entitled to the protections of the Code but that the Code is also really more of "guidelines" than actual rules.
Well, that attitude might work if you're captaining the Black Pearl. But it's not a good one to take if you're a writer looking to submit your fiction to a publisher. They may call their guidelines "guidelines" but if you don't want to shoot yourself in the foot, then it's best to treat them like hard and fast rules.
When I first started writing and submitting fiction, last millennium, this wasn't really that hard to do. At least as I recall it, there was a generally accepted "standard" manuscript format. William Shunn has an excellent web page detailing this format. Back then, you made sure your document looked like that (whether it was typewritten or word processed) and then you slid it in an envelope (along with a self-addressed stamped envelope for return of the manuscript or, if you sent them a disposable copy, for their reply correspondence) and took it to the post office and sent it on its merry way. (It's probably a drop in the bucket, but I suspect that among the various lost revenue sources the Post Office has seen, at least a million dollars a year has been due to the transition from paper to electronic submissions for fiction and poetry.)
Now, there are still lots of publications which want submissions in that same format. That's my default format when I first move a piece of prose from Google Docs which I use for my first drafts to a word-processing file. However, there are also many exceptions. Each time I submit to a publication for the first time, and often even on subsequent submissions, I check to see exactly what format they want to receive it in. Some publications want single-spaced but with an extra space between paragraphs. Some publications want Times New Roman, specifically, and not Courier. Some request that you not put anything which would identify you in the submission file, leaving that entirely for the cover letter which goes with your submission. And so on, and so on.
To someone who just picked up short fiction submission in the last few years, this probably doesn't seem at all unusual. After all, it's just How Things Are Done today. But to someone who "grew up" with a more rigid standard, it still seems a bit unusual.
But, as I said a moment ago, this variation now is simply How Things Are Done. And a sure way to get the person reviewing your submission in a bad mood before they even start reading it is to have blatantly ignored their submission "guidelines." And, putting myself in their shoes, there are good reasons for this. For one thing, it shows a certain lack of professional respect for the other party in your proposed transaction. They've taken the time to say how they want to receive your submissions and you've either failed to look for their requested format or failed to follow it. And, from a practical perspective, sometimes the requested format is so the editorial team can easily review submissions using whatever technology they have set up on their end. If having your submission in a non-standard format makes it hard for them to read your story, then that's not a good thing either.
In the end, most editors have so many times more submissions than they have available slots that it makes sense that they'd tend to not give the benefit of the doubt to someone who already appeared to not be taking their publication seriously. So the onus is on writers to read and understand the guidelines. And then treat them like rules.