I find myself going "huh, it's getting a little warm" at about 5:45pm, at which point I check and remember it's a "Rush Hour" session.
Not every solution works in every situation. That doesn't mean it doesn't work, it just might not work for you.
(Posted from a location that was 108° last week.)
Depends on the shape of the temperature graph for the day, the power of your AC system, your insulation, etc.
If your on a day that doesn't get below 90 and gets above 110 during the hottest part of the day and your AC is barely rated at the minimum recommended for your square footage and you have average insulation, no, and even regular AC use is going to be marginal and your AC is probably going to frequent service.
(And the things that make precooling work better also will make your AC work better and, for the most part, more energy and maintenance cost efficiently when you aren't precooling.)
If you live in a place where you frequently need AC, aside from decent insulation, getting an overrated, high-efficiency unit (which seem to be correlated for residential units, probably because both drive up cost, and there is a correlation between people looking for more capacity and people concerned with efficiency) is a serious quality of life improvement.
Later in the evening, it drops lower to be able to sleep, but also cool down the house, and taking advantage of the coolest part of the day for best efficiency of the AC system. It stops holding that temperature around 7-8am and goes to a much higher set point.
The house stays dry enough through the day that it never really gets uncomfortable, especially with a gentle breeze from a small, quiet fan in the room.
Earlier in the year in Australia when day time temperatures were 35°C-40°C (95°F-104°F), waiting until midday to turn on the AC would mean using another 10 kwh more than if the AC was turned on at 9am.
Granted, this is an new Australian house which means it's built to standards about 30 years behind what you would expect for a first world country.