I agree with the 2-5x comment, but I don't think this is the right way to look at it. Taking it to an extreme to demonstrate the point - a good team working on

I agree with the 2-5x comment, but I don't think this is the right way to look at it. Taking it to an extreme to demonstrate the point - a good team working on a large project could also just implement a new, more expressive programming language than Java and use that to implement their application. The whole point of language selection is to begin with a more capable toolset.