Does grammar matter?

Just last week, I was meeting with a US-based publishing rep, who flipped through my book and said, "Uh oh."
"What?" I said in trepidation.
"Your English can be quite a problem." He pointed at a few passages. "Some of this is quite literary, you see, and in selling popular fiction, your grammar might work against you."
Oh. I didn't know grammar could ever work against you.
But apparently, sometimes it does.
"You see," said the rep, who is a 6' 2" blond, blue-eyed hunk by the way, "they prefer to segregate literary books to literary publishers and popular fiction to pulp fiction publishers and so on. You have a mixture of these in your stories. That's a problem."
Oh.
I had never been told my English was a problem before. I only considered 2 stories in Dark City to be semi-literary i.e: 'Monster' and "The Scarlet Woman.' The rest were, well, pulp fiction.

In 'On Writing', Stephen King's book on, well, writing, the cardinal rule of any popular fiction writer is to tell the story without any fanfare.
"Write 'he said'," says King. "Don't write 'he said, desperately.' Just tell the story with minimal words and fuss possible."

And apparently, someone else was complaining about my grammar. The Malay translator was having problems translating Dark City into Malay.
"We're going to lose some of the gist of the original book," my publisher warned.
"I'm OK with that," I said, desperately. "You'll have to snip out the sex bits anyway and sanitize the book for the Malay version anyway."

But in writing for newspapers and magazines, grammar does matter a lot in fact. And if you're an unknown author, just to get the publisher to read your book is an achievement that goes with good grammar.

The moral of the story?
If you're writing literary fiction - let your grammar flow. (It would also help if it was a great story, like Margaret Atwood's 'The Blind Assassin.')
If you're writing pulp fiction - don't embellish it too much. Just go with the basics. The story matters most of all. Your grammar doesn't.