I suspect that it went into Autostop because it warmed sufficently and did not have anything do with the defroster. That might have just been a coincidence. EV mode is totally doable (I've done it up to 68
MPH) as you'll see in the other posts. But it does take some practice and it solely dependant on how much load is on the engine.
Also, it's nothing like the Prius, and frankly, I am not sure what all the fuss is about.