Who cares about Yahoo anyway??? I've never been banned by any search engine or affiliate program for that matter.
Yahoo needs all the revenue they need, wonder why are they out to banning sites, unless it against there TOS.
If your site has been banned by Yahoo, you can always email them for queries...ask if your site can be retrieved. Or you can always buy another domain and then start promoting your new site once more...and never repeat the same mistake again so as to refrain from being banned.