I know it won't be a problem
But somehow I'd be worried a phone that large that's thinner than the 5/5S might snap in half if it gets bound up in your pocket in the wrong way when you sit down!
The challenge of developing a battery slim enough for a 5.5-inch iPhone, nicknamed (暱稱) the "iPhone Air" by the parts-supply industry, may push that handset's introduction back until next year. So reports the Chinese-language news service Commercial Times (Google Translate). The same article also reports that a 4.7-inch iPhone …
I'm afraid I have to contradict you there. It might be a problem, because the magical powers of St. Steve are not around any more. When he was on earth, things happened according to his commands (even if the commands changed at some point...). TC doesn't seem to have this ability.
Jobs would not have this problem, The launch would always have been later, the phone always been thicker, or the battery always been of a lesser capacity, because it would have been better due to the fact that it was Apple.
The magic is gone.
>I would keep the phone width the same as it is and make it tougher with a larger battery capacity....
But if the phone is made thinner, the end user is free to choose from a plethora of after-market cases, allowing them to pick one that offers the best compromise between protection and bulk for their own situation. Someone on a building site might choose a bigger case than someone who works in a carpeted office, for example. Batteries and external battery packs, likewise - some people send their days closer to a phone charger than other people do.
>tougher
toughness is not the same as rigidity. I seem to recall a proverb about a sapling and a mighty oak in a storm...
Dave 126 has the right idea. Those who want a more durable phone or with longer battery life and don't care about weight/thickness are free to add an aftermarket case to provide one or both. Or choose another brand, like the Razr Maxx or that one company that sells "contractor grade" phones that can be dropped from 30' onto concrete.
Some of us have no problem at all with the battery life on current phones, and aren't in the habit of dropping them on concrete like those durable old Nokias. Not all of us wish to compromise for others' needs by having a heavier phone with a unbreakable plastic shell.