Across ten swept parameters, the burner's engineering gain is flat to within 10% over enormous ranges — a factor of 6.7 in length, 3.8 in density, 4.4 in throat field. It is a wide window, not a fragile point. The catch is that the width comes from those parameters barely mattering.
Nine of the ten parameters — length, density, field, radius, fuel mix, beta, temperature, converter efficiency, channelling — move the gain only modestly, so the design degrades gracefully rather than tripping a cliff. But none of them reaches closure either. Only the tenth, the plug density ratio, moves the gain by a factor of 11 and is the one that reaches net electricity.
A wide window is genuinely good for operability, and the burner has one. But publishing that the width means most knobs are inert — and that a single knob carries the closure — is the honest reading, and it points every experiment at the right parameter.
| Flat within 10% | 9 of 10 parameters |
| Length range flat | factor 6.7 |
| Density range flat | factor 3.8 |
| Field range flat | factor 4.4 |
| Reaches closure | plug density ratio only (x11) |