Most new cars these days have some prediction software that tries to sense if the driver needs engine braking when going downhill to save the brakes from excess wear and overheating. I think they look at how the throttle/brakes have been used and possibly the incline. On my VW, it will more/less freewheel down a hill, until I touch the brakes, then it will start to downshift/engine-brake from this point forward as long as I don't touch the throttle.
If it bothers you, I'd experiment with how you're using the brakes/throttle on various inclines and see if you can "fool" it into letting things go more.
What I am able to do is predict how much traffic will slow on the highway by looking at the cars in front of the car immediately in front of me and their brake lights. Ill let off the gas and let it coast. In city driving, if its a red or yellow, Ill slowly creep up while aiming for that 40MPG sweet spot. I had an CVT Civic before the CX5 and boy was the MPGs great on that car.