I noticed that the behaviour for mock image building has changed now with tim present. Pre-tim, a mock image build was practically a no-op however now with tim in place, the template actually builds a image when I request a mock build.
sloranz mentioned there are two type of mock builds for imagefactory and in order to get a fake build (like we did pre-tim), we would need to edit the templates os name (to FedoraMock or RHELMock) which I assume we would want to do on the fly as we pass the user's template to imagefactory.