Yahoo! Search is using a second link-only banning method in which the site's pages are not indexed by the search engine but links to the site that have been found on other sites are still included and can theoretically be found in a search. The pages have not been indexed so text on the pages cannot be found in a search. The pages are not cached. No descriptive text is provided in the unlikely event that such a listing is included in a search result, so a user is unlikely to be able to determine what the site is about. The title text provided in the search results is the "link text" provided by the site linking to you. These "supplemental results" are essentially useless for search users and are apparently included so Yahoo Search can claim to have a larger index than its competitors. If the site: search reports many pages, check to see if the listings consist entirely of "link-only" entries. Your site is banned if the search engine is not indexing your text. The link-only entries result from indexing other people's sites. Link-only banning adds insult to injury. Yahoo Search is claiming your pages as included in their index while actually refusing to index them!
Another test method is to search for some unique phrase that appears only on your pages. Some webmasters include a phrase such as “Vmxzwh S34pp” on their pages for this purpose. This search will avoid listing “link-only” entries and will also disclose some of the other sites (not banned by the search engine) that have stolen your content, if any.
The “ultimate misfortune” is to find that your site has been banned but that many sites that have stolen your content have not been banned by the same search engine!
We would expect that spiders would stop visiting a censored site. They do visit much less frequently. However, they usually continue to access some pages and to check /robots.txt apparently to monitor that the site still exists. Yahoo’s robot “Slurp” checks /robots.txt up to several hundred times per day. One reason for doing this might be to determine if a domain name is sold to another owner by detecting a substantial "down" period.