the difference in density between 100°F and 170°F air at sea level pressure and the same humidity ratio is about 12%, so in theory the engine should be able to draw in that much more air mass at a given engine speed and throttle position. That's the physics of it.
There's an IAT sensor so the ECU is doing something with it, and even if it didn't, the air mass ought to push the mixture lean and induce a response in the STFT via the O2 sensors. But we don't really know how much more heat the charge picks up after the IAT sensor. Probably much smaller than the original difference at the air filter at least.
I swear there's something that feels more crisp about my TJ when I drive it on a cold morning with sub-100 IAT's vs a 105 degree day with IAT up around 170. I can't blame the fan because I still feel it at highway speed. I'm not sure I can tell any difference in WOT performance, but I don't really go WOT because it doesn't feel any stronger than about 60% throttle anyway (which leads me to believe the throttle is no longer the restriction once I get that far, hence why larger TB's are useless).
The best I can come up with is that due to the density, I may just be reaching the same mass flow at a slightly smaller throttle position. As has been touched on earlier in the thread, a more consistent IAT makes more consistent emissions, and that's probably why Jeep did it.