Both. There is (or was) an established Systems Engineering body of knowledge with methods how to do systems analysis and in parallel synthesize the system and process architecture. But there were actually no decent tools to support it; most tools were actually just drawing tools or expensive text editors (e.g. DOORS). And the few PM tools (e.g. Microsoft Project) stopped working properly when there were thousands of tasks. So we had to somehow cope ourselves with the immense, permanetly changing amount of information. Today there are much more tools and possiblities to implement tools for large projects, but I have the impression that in the last ten years many methods have been forgotten or watered down beyond recognition.