The idea is to submit unique articles to all directories, so as new article directories come along write out a post and submit it with your link, before you know it you have 1000 links, lower end article directories will not hurt you at all!
What will hurt your rankings is black hat, and doing article submission to multiple new directories is not considered black hat, they are not going to go devaluing people sites for submitting to these article directories, they are going to credit you
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Submit your highest quality articles to sites like Webpronews, Ezinearticles, and etc. When you submit your articles to even the lower quality directories they show up in Goggle, and therefore you never know when your article could pop up, plus its a back link like a I was mentioning earlier.
Keep them unique!