initially, being in the loop is necessary, once you find yourself "just approving" you can be relaxed and think back or, more likely, initially you need fine-grained tasks; as reliability grows, tasks can become more complex
"parallelizing" allows single (sub)agents with ad-hoc responsibilities to rely on separate "institutionalized" context/rules, .ie: architecture-agent and coder-agent can talk to each others and solve a decision-conflict based on wether one is making the decision based on concrete rules you have added, or hallucinating decisions
i have seen a friend build a rule based system and have been impressed at how well LLM work within that context