Wouldn't you would want to be seen as thoughtful of the editors' time demands when considering the merits of a submission and its fit with a particular issue? If you haven't followed the guidelines, might we fairly assume you haven't read past issues or have any idea of the kind of work we publish?
We are not trying to limit your freedom. We do not want to make your life more difficult. We have these guidelines because we want to give each submission the best chance of an unbiased and positive reaction.
If we've asked for Arial typeface, size 12, why would you ignore that request? Aren't you at least curious about that choice, when you're so familiar with Times New Roman? This matters a great deal because we read submissions onscreen, and Arial size 12 is the best typeface and size for comfortable online reading (we receive more than a thousand submissions per submission period). The familiar serif typeface of Times New Roman ("little feet and embellishments on the tip and base of each letter") is fine for print, but more difficult to read online. Arial's "sans-serif" typeface (no embellishments), size 12 or larger, doesn't use as many pixels and is easier on the eyes, especially for long hours of onscreen reading.
I'll let you in on a secret: I hate Times New Roman. Even on a good day, when I'm feeling patient and haven't yet read ten submissions of up to 2500 words each, I still have to suppress my Times New Roman bias when I hit Ctrl+A ("select all") and change the typeface to Arial so I can read it with my already fatigued eyes.
