You don't need to worry about disavowing spammy links.
This site was maxing out their disavow file by disavowing every spammy link they could find.
Jan 14 Google help hangout
youtube.com/watch?v=GZ_wSe
#SEO
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Yep. Disavow file is better used for previously bough link schemes that you're unable to get taken down or nofollowed.
Recommended this recently to a client and worked like a charm.

