If the manufacturer tells you, "Hey your device will last two to three days depending on how much you move" and you realize that it only lasts two for you AND then you don't charge it on second days AND proceed to bash the product because "ohhh it kept running out of battery and what's the point of analytics hurr durr" you're officially a retard.
You want to complain in a review that the estimation of the battery life sucked for you, fine go ahead, I have no problem with that. But make an objective review and actually try to use the product instead of just using the first scapegoat excuse you can get to bash it into the ground.
If it had been a negative review because the product is bad I'd be the first in line to commend the reviewer for not spewing a bullshit from a product marketing sheet. That being said, this is not a good review, it's FUD all the way around.
Regardless, a hopelessly optimistic battery indicator is a bad thing.
iPod touch and iphone here, but if the devices don't even talk to the phone during the night, I don't see how that variable makes a difference.