The spec prompts are typically better off being reviewed iteratively using AI itself, a lot more so than merely by pairing with coworkers. Perhaps a combination is best. The point is that AI reviews of the task spec must never be overlooked prior to its execution.

Also, if your spec is taking too long for the agent to execute, odds are high that it's ambiguous, unsound, unreviewed, underspecified, unmaintainable, or the model is just optimized to waste tokens so as to bill you maximally.