How involved is Hans Zimmer in his films' music?

We know that the approach to the four Pirates of the Caribbean movies, as well as movies like Rango, was basically: write some thematic suites that encapsulate the tone of the movie, other composers use that thematic material to write the actual score of the movie under his supervision.

I have theorized that Zimmer may take a more active "real composer" role in the movies he's done for Nolan, aside from occasional help from trusted collaborators like Lorne Balfe, who we know contributed to Inception.

But what about the movies that Zimmer couldn't possibly be bothered to write even a suite for? For instance, Zimmer is credited as sole composer for all three Madagascar movies. But does anyone really believe he wrote even a single note of music for those films? If anything at all, it amounted to "here's 3 minutes. Interns 1-5, write the other 70 minutes." Rinse and repeat another two times. Basically the Pirates approach, but with far less work put in.

Ditto for Call of Duty: Modern Warfare 2, where it's generally accepted that Zimmer wrote the "main theme", and Lorne Balfe wrote literally everything else. In which case, crediting the score as being composed by "Hans Zimmer and Lorne Balfe" feels like a sick joke.

But I'm not certain even that level of involvement would be required. Contracts are a beautiful thing. They can be written in a way that doesn't mandate Mr. Zimmer actually create any music himself, but he's still credited as sole composer.

What do you think? I know music is a relatively niche aspect of the filmmaking process, but I'm sure some of you here are interested in it, and some of the you who are interested in it also know about the widespread practice of ghostwriting film scores. A practice largely pioneered by Zimmer.

This is not a "hate Zimmer" thread. The man is supremely talented on multiple facets. But he is pretty much the exemplar of "work smart, not hard" in film music.