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[oskar]

So he's talking purely about the EF from the battery inducing a theoretical current in a theoretical 0 ohm lightbulb? Induction wouldn't be instant, neither would be capacitive coupling, and both would only make the bulb blink once.
So the entire circuit is just misdirection?

[OngBonga]

^ that is...

1/c tells us how much time it takes something to travel a given distance at the speed of light.

c tells us how much distance something travels in a given time at the speed of light.

[OngBonga]

So the entire circuit is just misdirection?

Sort of. The circuit allows electrons to flow, and the flowing electrons create the electromagnetic field necessary for the flow of energy. Without a complete circuit, electrons don't flow and energy cannot be transferred electromagnetically. So the circuit is an essential part of this system. But it's misdirection in the sense the energy does not flow round the circuit. Well, some does, very slowly, and it's a tiny amount related to the charge of the electron, not the power of the source. The energy flow from battery to bulb is through space, not through the circuit.

What I struggled to get my head around is how an electron can instantly "know" a circuit is complete. But the conclusion I came to is that the circuit was completed, except for the switch, in advance, and so the entire circuit is already electrically primed, for lack of a better phrase. The electrons have already "communicated" the electrical status of the circuit. The switch is merely the final piece of the jigsaw, and that information moves through space at c. If you were to cut the circuit in space, 0.1 light seconds away, then the EM field would collapse, starting where the break is, and propagating at c, reaching the bulb in 0.1 seconds.

Not sure if you're following what I'm trying to say, it's not easy to explain, especially given I'm basically guessing.