Yes, when stumbling across bad code, the first instinct should be: how can I make this simpler. Not how can I wrap this bad code in more convoluted patterns. Don't use a big word when a small one will do.

Additionally, I find that the key problem with bloated models stems from missing domain models (often has-many-through models). Not from moving the logic of the existing models into more noun classes. In your example here, the purpose of the ticket is to tie a user to a grouper: that's exactly the place to put logic that governs that connection!

Finally, what gets my goat is this notion that these patterns are necessitated by "advanced deployments". As it was some law of nature that when your app hits a certain size, you have to introduce this litany of misfit patterns. That's like arguing that if your book is longer than 300 pages, it must also use really big words and complex sentence structures. What?

The solution to large applications is to double down on simplicity, not give up on it. It is even more important to get the basics right. Execute them beautifully before even contemplating to freewheel from there.

Just food for thoughts, I forked DHH's implementation and modified it to support a bigger structure (so you can keep stuff in different files/class). I haven't tested the file so it may contains bugs, I apologize if it does.

The file name contains dash(-) replace them with slash(/) as github doesn't like path.

https://gist.github.com/pothibo/9673715

I hope you like it ;)

Edit: It had a shit loads of typos, I believe I have fixed most of them.

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.

But if you have a beef with how much of the domain logic is in the Model, don't blame Rails, blame MVC. I mean, come on.

Either you want to use MVC or you want to go in a different direction. Fine. But don't blame Rails for being a good MVC implementation. Instead, formulate your own, new "philosophy" about how this all should work.

While I don't generally acknowledge the validity of "Before you criticize, think of something better", in this case I think it's appropriate. You appear to be critical of the whole MVC philosophy. And that's FINE. No problem. But before you go criticizing Rails I think you should formulate your own philosophy of how it all should work instead, rather than blaming Rails for doing what it is supposed to do, and doing it well.