You're onto something, but be careful. Bicyclists who want to be competitive learn more than the average athlete about exercise physiology, because, after all, you is the engine, man.
I generally don't buy gatorade and such, but i think maybe in the heat like this it may be a good idea. I did put down a couple banannas, a Myoplex bar, and a turkey sandwich during the evening too.
Water by itself, as badly as you need it in this weather, doesn't empty from the stomach and get absorbed as fast as solutions containing a small amount of sugar. The simpler the sugar, the better, since only monosaccharides like glucose, dextrose, and fructose can be directly used as a fuel source (not entirely directly, but they drop right into the process without modification). Disaccharides, like sucrose (table sugars) have to be converted to monosaccharides first, so they get delayed.
Anyway, stuff like Gatorade and soft drinks have too much sugar, and swing the balance the other way, with the same result, they don't drain from your stomach very well. The answer is to find a level of sugar that meets your individual system's idea of isotonic, or the ideal amount of simple sugar to cause the fluid to empty from your stomach and be absorbed and used rapidly.
Gatorade at around 50/50 with water is a place to start. A lot of cyclists used to use watered down fruit juices. My current favorite is Arizona Iced Tea's Green Tea cut with water so it's 65% tea and 35% water, and alternate between that and water from the Camelback.
Makes a big difference.