You must have a magic coil there. I tried low-speed fan as an experiment. The air out of the register turned warm and dank very quickly.

The fan probably runs a minute or so after compressor shuts off. After that, the low-speed fan takes over. Quickly disabled that feature/.

V

Maybe helps a little in arid climates. In any kind of humidity, don't even think about it.

The claim is up to a 30% savings by turning off the compressor a few minutes early. I think savings would be closer to 3% than 30%.

To be fair I think their claim is to save 30% by all the features, not just this early shutoff. I've heard about this stat and it's supposed to "learn" your home/away patterns to use minimal energy. Wouldn't work for me as we often have completely random home/away hours. I prefer to program something and have it work as I expect I don't want it trying to make decisions for me.

Seems pretty clear from the web site I've linked that they are claiming 30% savings from Airwave alone.

What is Airwave?
Airwave�, an exclusive feature of the Nest Learning Thermostat, can automatically lower air-conditioning costs up to 30%. Airwave only works in homes that have air-conditioning.

Nest Airwave is most suited for regions with dry climates and low humidity, such as Arizona and similar areas. It utilizes the evaporative cooling effect of dry air left in the ducts after the compressor shuts off to reduce humidity and improve indoor air quality. It may not work as effectively in areas with high humidity, such as North Carolina, as it can potentially pump humidity back into the house, making it less comfortable. Therefore, it's recommended to disable the Nest Airwave feature in humid climates.

Talking of Florida, can airwave reduce energy while cooling?

Florida is known for its hot and humid climate, with high levels of humidity throughout the year. Therefore, it may not be the most suitable region for Nest Airwave to provide energy savings on your air conditioning bill, as the feature relies on evaporative cooling effect of dry air in the ducts, which may not be as effective in high humidity environments.