Over at Dear Author there was a review of a book that apparently was a complete rip-off of a better book. She didn't just rip off the basic plot but apparently ripped off the scenes and little instances in the original.
Some commenters said that they were always nervous because they've read so much romance that their original ideas might be, in fact, not original at all.
Years and years and years ago when I was dewy eyed and randomly lustful, I took a creative writing class with a babealicious teacher. And by happenstance, he and I ended up having dinner one night and discussing getting published. His advice to me, in talking about writing Harlequins, was to copy one word for word. Just type what someone had already written and then do it again.
His point was that I would learn what that writer did that was successful but writing out her book. Then I should go write my own.
When I decided to write earnestly, I tried to do something similar with a Jayne Ann Krentz book. Or any of them. She has a distinct format and so I decided to copy it. I wasn't successful but again, the lesson for me was pretty clear.
I'm not suggesting that what the bad writer above did was this but it sounds like it. She took something that worked and then tried to rewrite it and make it her own. She was unsuccessful.
If she'd been a better writer or more creative perhaps, she could have taken the original book and used it as a starting point to create something her own. It's okay to read something and think, I want to steal that. The idea is to steal it by recreating it in your voice and style and making your readers know it's all you.
It's the difference between a hack and a writer. That lady was a true hack.