I came up with the following description a couple days ago. This relates to A-B-C linking with a blog directory:
Smart Linking (also known as A-B-C linking) is a way to get a higher ranking on search engines: you place 8 links on your blog that point to 8 blog directories. But these 8 blog directories won't link to your blog. Instead 8 other blog directories will link to your blog. This way we are not trading links directly, this will result in a higher search engine ranking for your blog.
Blog Submitter now does support A-B-C linking:
http://www.adultblogresource.com/submitter/