It depends largely on how you're inputting the stories.
If you are writing in Word, you can use the No Spacing style to remove those extra lines between paragraphs in your document. It will look impossibly awkward without spaces between paragraphs, but when you post the story by pasting it into the Rich Text Editor, it should come out fine.
The other option is to manually delete them in the Rich Text Editor. They will show up there when you paste the story initially. It's a bit time consuming to remove them like that, but again, once you have the text looking the way you want in the RTE, it should appear that way in the archive as well.
If you write in LibreOffice or OpenOffice, I believe you can emulate the No Spacing style that Word uses.