◇ Could this help me?
Yes. This is the same economics as ordinary model routing, applied through orchestration rather than by hand, and the reasoning holds: most of the value of an expensive model is in deciding what to do, and once that decision exists a cheaper model executes it perfectly well, so paying premium rates for execution buys very little. Running the sub-agents in parallel is a real speed gain on top of the cost one. Two caveats: the claim that the output is indistinguishable is the creator's impression rather than a measurement, so verify it on work where a subtle quality drop would matter, and a tool that edits your project instructions by default is something to opt into deliberately rather than accept as a convenience. General practice.
I want to use my most capable model as an orchestrator rather than as the thing doing all the work. For the task below, act as the manager: do the hard reasoning yourself, which means analyzing the problem, deciding the approach, and identifying the risks, then break the execution into independent pieces that a cheaper, faster model could carry out in parallel. For each piece, write the instruction precisely enough that a smaller model can follow it without judgment calls, and tell me what you would check when the results come back. Flag any piece that actually requires the stronger model and explain why it cannot be delegated.