That's true if we're talking about the overall architecture of the project. And, since R permits so many different coding styles (and paradigms: native function

That's true if we're talking about the overall architecture of the project. And, since R permits so many different coding styles (and paradigms: native functional and several OO), the team should have someone (usually the most senior software engineer) play the role of an architect and design the structure of the code, data structures, API, and so on. Perhaps having a fixed (and commonly agreed on) set of design patterns - like in Java - makes development easier and smoother, but most of the projects I've worked on have proven successful, so maybe it's not that bad either... :-)