We had a case at work for not doing this. We had a section of our app where users could set up their profile, for example /user/profile (scoped to them by their session). Imagine it is more than just CRUD, and has a few bits of complicated logic (in reality there are multiple controllers - it's a big profile :D).
We then wanted to add the ability for admins to edit profiles, so we created /admin/users/[id]/profile. If the logic wasn't in the model we would have to repeat it in both controllers (the views can easily be reused by having the form elements in partials).
Of course — complicated logic is a good hint that code maybe should be moved somewhere else, be it the model or some manager class. Just like you moved (or maybe had from the start) the form elements into partials. It's probably not something to obsess about too early.
The thing that bugs me the most is how both the article and some responses here go into heavy absolutes. Different domains have different needs, and what is "readable" changes between them, not just by size, but by shape as well. And yes, shape and size might change as the app lives (my current codebase being a great example), but you can't really predict everything.
We then wanted to add the ability for admins to edit profiles, so we created /admin/users/[id]/profile. If the logic wasn't in the model we would have to repeat it in both controllers (the views can easily be reused by having the form elements in partials).