I think that what you have to do is use the more tag. Whe you write a post or an article, at the end of the first paragraph, write this:
If you do, then the whole article does not show over and over again. Only the first paragraph shows as a summary and only the page with the actual article shows it in its entirety.
Personally, I think the blog looks neater and tidier using the more tag even if there wasn;t a duplicate content issue.