Selected answers from the Dumb SEO Questions G+ community.
David Harry: since we don`t get notified of when it`s crawled, I don`t think there`s any way to tell
Tony McCreath: Google have stated that the new Penguin algorithm only discounts bad backlinks. Which indicates that the disavow file has no value there anymore. With a manual backlink penalty it could help your case.
Bill Hartzer: If Google has cached the page that you disavowed then they have disavowed it. There are ways to force google to crawl your disavowed pages. ;)