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There is a plausible route from real physics to that wording, which is worth laying out because it makes the phrase less mysterious.

Temperature genuinely does affect transmission lines. Conductors expand when hot, so spans sag more; sag changes clearance to whatever is below; and a line's current-carrying capacity depends on how well it sheds heat to the surrounding air. Large temperature swings therefore change what a line can carry and where it physically sits.

There is also a real mechanical phenomenon in which wind causes conductors to oscillate — galloping and aeolian vibration are the standard terms, and both are studied extensively because they damage hardware.

So you can imagine an explanation involving temperature, atmosphere and oscillating lines getting compressed into a phrase for a press conference, by somebody working from a summary rather than from an engineering report. That is speculation about the wording rather than about the event.

The argument is sound as far as it goes and it fails on one crucial point: it assumes your heating converts electricity to heat at the same rate the bulb does.

If you heat with a resistive electric heater, that is true. A joule of electricity gives a joule of heat either way, and in that specific case an inefficient bulb genuinely costs nothing extra during the heating season.

But if you heat with a heat pump, it is not true at all. A heat pump does not convert electricity into heat — it uses electricity to move heat from outside to inside, and it delivers several units of heat per unit of electricity consumed. Three or four is typical, more in mild conditions.

So the bulb's waste heat costs you one unit of electricity for one unit of heat, while the heat pump would have delivered that same unit of heat for a quarter of the electricity. The inefficiency is real and the ratio is large.

Worth mentioning the non-physics reasons, since they explain why the argument never ends.

Over is generally easier to see the end of and to grab, and it keeps the paper off the wall — which matters if the wall is textured or dusty. Under is harder for cats and small children to unspool onto the floor, which is a genuine and much-loved argument in some households.

So the physics favours one, and the household constraints occasionally favour the other, which is exactly the situation in which people argue forever.

One historical detail that makes the bootstrap feel less abstract: much of it happened in workshops rather than laboratories, driven by needing better machine tools.

A more accurate lathe lets you make a more accurate leadscrew, which lets you make a more accurate lathe. That loop ran for generations, each turn improving the next, with the three-plate method and reversal tricks used at every stage.

It is one of the few technological ratchets you can trace step by step, and the people who turned it mostly did not write papers.