[ollysb]

The theme I'm seeing in this series is a desire to add a layer between controllers and the domain. This new layer seems closer to the controller than the domain (it always acts upon the domain) so are you not simpler making the controller layer thicker? By removing logic from the domain you're creating a distance between the information and your business policies. For instance you now have to remember when to apply particular policy objects. If the logic lived in the domain then the objects would take care of this automatically.

Fundamentally I have an issue with this whole approach, if you have bloated domain objects then organise them better (as DHH mentions a common problem is not having enough classes in your domain). Also, given the choice between bloated objects and logic separated from it's information I would take bloated objects any day.