If your '04 Corolla has 437k on it, there is a slight chance that a few of the ponies have slipped out of the stable over the years.
That and the 4AT with its limited gear ratios (all 4 of them, which is less than that when you put your foot into it, you have what 2 and then you're not far from top speed?) does mean just what you say, these CVT's can now put the rpm where the ECU thinks is the best spot for the power requested--it now has control over throttle opening, valve timing, spark and fuel, and now even the RPM.
I'm not sure I've gone flat out in mine (fears of the glass CVT!) but it seems to do fine against my '99 Camry with its *ahem* 138hp and 4AT. While being around 40mpg (haven't checked in a few days, the readout has dropped, maybe it's time for winter gas?).