In general a Full Stack DevOps oriented approach always tends to be more efficient. You have less monolithic hard to maintain applications because you force the teams to be small and agile. People will have their specialties (operations, backend, frontend, etc.) but still remain generalized enough to have an idea of the big picture. If your application has issues where the frontend developer doesn't know the general idea of how Varnish and Nginx in your stack are setup then perhaps your application is too big and complex.