Originally Posted by Paz

It's only useful when you have a link penalty, and I've had a few, and even then you have to get a susbtantial number of links taken down, document everything and write a "I'm sorry promise it won't happen again" covering letter.

Stuff in a disavow does eventually disapper from the Webmaster Tools but it takes a long time; so long I can't even remember but I think it was 6 months to a year.

Disclaimer: Every site and market is different though, I have no experience of link building in adult and I'd be interested to hear other opinions.