There are more than ten rules/commandments. Actually, there are ten from several different authors. Some of them are complete bunk. Some of them are gems of wisdom. I haven't (yet) come across the one that essentially reads: "Break the Rules", or "Tell the Rule Makers to STFU", but I'm hoping they're in there.
Elmore Leonard (of whom I have never heard, but now I have someone to look up) has two rules of especial note:
3 Never use a verb other than "said" to carry dialogue. The line of dialogue belongs to the character; the verb is the writer sticking his nose in. But "said" is far less intrusive than "grumbled", "gasped", "cautioned", "lied". I once noticed Mary McCarthy ending a line of dialogue with "she asseverated" and had to stop reading and go to the dictionary.
4 Never use an adverb to modify the verb "said" . . . he admonished gravely. To use an adverb this way (or almost any way) is a mortal sin. The writer is now exposing himself in earnest, using a word that distracts and can interrupt the rhythm of the exchange. I have a character in one of my books tell how she used to write historical romances "full of rape and adverbs".
Now, I can somewhat see what he's getting at there - there are definitely those who go overboard. At the same time, I fail to see why I can't use adverbs if I damn well feel like it. I've always used adverbs, to one degree or another. I try to keep them simple, just because I want dialogue to flow properly, but eradicating them entirely just seems...stupid. Plus, it's probably a personal foible, but I've noticed that, in the midst of books that follow those two rules, I find myself wondering what emotions I'm supposed to be feeling.
(One of) the most important thing(s) about writing is to find your own voice, that thread of style and phrasing and diction that screams to everyone that this work is yours, and no other's. Part of my 'voice' is the use of adverbs. So Elmore Leonard can lump it. He also writes westerns. So hah.
Seriously, though...the best rules about writing to follow are the ones you come up with after long years of practice. Everything else is merely a suggestion, and can therefore be treated as such.