From experience, both unreal and cryengine are perfect examples of Pieter's point. They're large codebase with archaeological layers of many different c++ styles and paradigms.
Please consider the precise argument I was responding to.
Pieter's point is a stronger statement than just the existence of "different styles". (Every significant codebase by multiple people has multiple styles -- e.g. see Linux distribution.) He was stating that there was a cause and effect such that the different styles ("dialects") cause "isolation".
If so, it means Apple's Swift compiler written in C++ on github[1] should be getting near zero forks and pull requests. In his theory, Chris Lattner and his dialect of C++ should be "isolated". It's also possibly unintelligible C++ (although I haven't looked at it yet).
If it was just one of those throwaway sentences to troll people, then fine. My first impression was that he wanted his programming guide to be taken seriously.
I enjoy reading C++ criticisms. The criticisms in the C++ FQA by Yossi Kreinin has interesting points. I'd prefer it if the faults of C++ were accompanied by evidence.
Yes, like I said, speaking from experience, different C++ code styles and paradigms absolutely do cause isolation. Having to climb yet another mountain in order to be effective on a different codebase in the same language means people don't do it, so they become experts in a single codebase -- isolated.
