I disagree, the company I work for is big but not massive and yet even using this kind of approach on a single product in our suite has been really beneficial. Its not as complicated as you may think, its just about keeping the code clean. Its allowed us to refactor technical implementations with much less risk and makes the code easier for people to follow. Sure it maybe a bit of a mental shift, but its not like you wont find benefits in it. (And I disagree with the insinuation that its more complex or slowing down development, I actually find the opposite is true).