Sand - 3:53 pm on Aug 25, 2012 (gmt 0)

a single editorial link on DMOZ could blossom into hundreds of links on hundreds of spam sites.

I understand what you're saying, but again, every site on the internet that's been around for a year or more has hundreds of spam links pointing at it from various scrapers and 'domain info' sites. If your site is susceptible to being harmed by those links, then that's indicative of a larger problem (either in the marketing or overall development of your site).

I know this is cliche, but it's true: if you create valuable content and market it to the people who care, your site will have enough positive signals that you don't need to worry about people scraping your directory links.