As advertised, this module provides Test::WWW::Mechanize and WWW::Mechanize-like functionality for testing Catalyst-based applications. I used it for Catable, the Catalyst-based blog engine, and it proved very easy to use and along with the documentation of Test::WWW::Mechanize and WWW::Mechanize, documented enough.
I do wish that it was possible to view all the available methods without having to look at those of the sub-classes in separate tabs, but I guess you cannot have it all.
In any case, if you want to test your Catalyst application, check this module out. It's much more powerful than using Catalyst::Test.