[revskill]

Sharing business logic between models/controllers/views often leads to a mess.

There's a reason to just write business logic code at only ONE place, the controller.

You'll thank yourselves years later when you revisited your code. Just one place to look for.

[conanbatt]

Long term controllers being fat will give you headaches if you want to provide an api for different platforms (mobile, another web)

[drizze]

But placing logic in the controllers means you need to get a rails controller to test your business logic. This may seem fine in a small application, but as an app grows it becomes a headache to need to tie all your business rules to your framework.

“Rails is not your application”

[revskill]

If "Rails it not your application", why use Rails then ?

[joevandyk]

It’s a set of libraries that work great together, it’s pretty easy to learn, and lots of people know Rails.