No, that is still not true, no matter how good the insulation.
> That fully depends on the level of insulation. Newly build houses here in The Netherlands rarely cool down when heating is off, and the temperature stays generally stable, even when you are out (and the heating is off).
Even if it's a few days, and it does drop a few degrees, you still spend less energy bringing it back up to whatever temperature than you would have to keep it there the entire time.
Do you have anything to support that claim? Because in my belief this follows normal thermodynamics, which means that if the energy dissipation over an amount of time is less than the energy cost to heat, it makes sense to do it.
Do you think there is no relation between the thickness of the insulation and the time it takes before reheating is more energy efficient?
> That fully depends on the level of insulation. Newly build houses here in The Netherlands rarely cool down when heating is off, and the temperature stays generally stable, even when you are out (and the heating is off).
Even if it's a few days, and it does drop a few degrees, you still spend less energy bringing it back up to whatever temperature than you would have to keep it there the entire time.