We've had very good performance by actively ventilating at night to cool the mass of the house. A box fan can move over 2000 cfm which is enough to drop the indoor temperature to within a few degrees of the outside early morning temperature after running all night. It takes a good 6 hours or so to come up to a temperature where we would even consider using the air most hot days - usually allowing us to keep it off and the house temp under 75F until 4-5 pm.
That said, our AC use is more often at-will, usually in response to higher humidity rather than temperature. So we are able to run it for shorter periods of time to dehumidify, then shut it off without really cooling the house off much at all.
No matter how you look at it though, it can be compared to a bucket full of water with a hole in the bottom. The more water (temperature difference) you have in the bucket, the faster you lose it, and the faster it needs to be replaced to maintain a constant level. The only hitch in that analogy is the effect of humidity which is relatively quick to remedy.
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