AI speeds easy code +40%, legacy monoliths +5% (or -5% in COBOL hell).
Stanford’s 100k-dev study: average win = 15-20%, mostly from boilerplate.
Faster shipping = 10× rework on bad ideas.
Real bottlenecks? Killer ideas + 6-week A/B tests.
Verdict: Use AI as turbo-intern; keep customer calls sacred.
