Well, I don’t follow ANY of the math in this thread, but if a real live honest to goodness mechanical engineer tells me it’s OK to turn my thermostat down at night, then I guess it’s OK.
Now to convince the Better Half, who grew up, as I did, with it drummed into his little head, “Don’t touch the thermostat! It actually saves energy if you set it and forget it!”
And actually, we live in such a big drafty house that it’s doubtful it’d make much difference in our heating bills anyway.