Hmm....I know what you mean...I've read stories that are actually really very good, original yet keeping realism. Then comes a sex scene that gets thrown by one silly or overused word (or more than one, that's happened too)and I suddenly loose interest in continuing the story. I've had moments where I was really into a chapter and something as small and simple as a single word has actually made my face contort. Strange how a word can have so much impact. Intriguing too...there should be a list of words that should never ever be used under any circumstances. lol.
And about the grammar/ spelling; that gets on my nerves too. My mom is an English teacher and, though my grammar is far from perfect, I think that as a writer things such as syntax, grammar and spelling should be taken just as seriously as things such as plot, character developement and movement of the story.
It's the details in the fabric that compile a true work of art, not the person doing the creating.
*shrugs*
That's what I think.