> The contol on the stove may be fully unscrewed, but the gas won't come out any faster
> due to the regulator. It is therefore the action of the regulator that allows a
> larger jet to be used with a given burner head size (giving the benefit when the gas
> pressure is low) without excessively large flames or lift-off when there is adequate
Agree, but everyone should note that you can achieve EXACTLY the same effect by simply adjusting the valve on the stove. A 'pressure regulator' and a 'needle valve' have EXACTLY the same effect on the gas pressure at the jet.
As with a propane system with its far higher tank pressure, the pressure regulator on these stoves is really just a safety device. Yes, it does allow the use of a larger jet size, but so what? A smaller jet gives the same gas flow when it has a larger driving pressure, and our propane/butane canisters have plenty of pressure (except when very cold, see below). The only difference is at those last few moments in the life of the canister, when all the liquid fuel has been used up and there is only gas left in the canister. Well, at that stage you are going to have to replace the canister in a minute anyhow.
There is a marketing myth promoted by some that a pressure regulator can somehow make a canister work *better* when really cold. That is a violation of the basic laws of physics, and just does NOT happen.