I have read a lot about programmable thermostats but can they really save me money? I have a 96% propane funace in Ohio. My home is well insulated and holds it's heat well. If I set a programmable thermostat to 72 for days, then 65 at night for 8 hours will I save propane? Some say it takes longer to heat the house back up and in the long run will cost more. What do you think? is it a money saver or a myth. Thanks