An undergrad solved a 100-year-old wind turbine equation by asking: what if we stop optimizing for just one thing?
Glauert (1935) maximized power output. Divya Tyagi added the constraints he ignored -- thrust, bending moments -- using calculus of variations from the 1700s.
Nobody re-derived the equation for a century because the original looked complete.
Hardcoded assumptions hide in plain sight.