More productive in what way? Letting agents burn tokens to produce garbage output is not productive. And letting teammates read code that wasn't reviewed by a human submitting it also isn't productive.
If I work with one agent / few subagents on one feature I can steer it as soon as I notice it drifting into the direction of waste. This way I only review the total diff 1.5-2 times. And I also don't waste my own mental energy on context switching between tasks agents are producing diffs for in parallel.