If the spec calls for a car, and I give you a car with a roof-rack, then I've exceeded the specification for what the car must do. Whether that's an improvement is subjective. If you don't need the rack, then your MPG suffers.
If the spec calls for a car, and I give you a car with a roof-rack, then I've exceeded the specification for what the car must do. Whether that's an improvement is subjective. If you don't need the rack, then your MPG suffers.