When I'm on the highway to/from work, I find that the radar cruise control does really well using EV mode as much as possible. I'm seeing the 60's as far as mpg on the highway.
Eco mode isn't "better" per se, but it does give you finer control over throttle demand at the low end of the pedal travel range, which is helpful if you're trying to hypermile (or anytime you want to actively manage when the ICE kicks in).
It takes more pedal travel to get the same throttle opening. In my (admittedly 3rd gen) experience, the increase in travel was excessive, actually making it harder/tiring to get the response you wanted. to be fair, I’ve read 4th gen reduced pedal travel signicantly, for all the modes. still, it’s quite simple what it’s doing; I noticed no mpg change going from Eco to normal, and found the latter more natural. Again, that’s with 3rd gen.
if you drive gently, looking for higher than average mpg's, you don't need much throttle in eco. for normal driving, i can see the aggrivation
Yes, on the 4th gens, pedal travel is so short overall that tiny pedal movements make a big difference, especially at low speeds. This makes it rather hard to feather the pedal just right to keep the car from kicking on the ICE when you don't want it to-- press just a tiny bit too far and it shoots up past the EV zone, wasting gas. "Eco" mode makes the response less linear, giving you more play at the lower end. This allows for finer control with less accidental overshoooting. Of course the tradeoff is even stronger response at the high end, but that's not an issue with how I drive-- if my gas pedal is more than a quarter of the way down, I'm probably flooring it anyway (for extra-short freeway onramps, etc). The first 25% of pedal travel is the only place where I actually care about finer control, and "Eco" mode helps there. This is all 4th gen. I've never driven a 3rd gen, so I can't compare, but it sounds like it was quite a different experience.
Toyota engineers don't design a mode for no reason. I don't have hard evidence since I didnd't record it but I did notice ECO mode is a bit higher MPG. YMMV
It has seemed to be a user interface thing. Different people do best with different choices of user interface.
I went pwr -> eco -> normal, and found that normal somehow works best for my lead foot dyamics to get better mpgs. Ultimately, it's about which mode let's you "slide and glide" best haha