To quote Corning "Introducing Corning Gorilla Glass 5, a new glass solution that raises the bar for protection against drops higher than ever, surviving 1.6-meter, shoulder-height drops onto hard, rough surfaces up to 80% of the time."
They then go on to say "...That’s up to 4X better in drop failure height than competitive glasses...". They seem to be very careful to say up to in both cases.
That caveat seems rather extreme. Unfortunately the published information only has a graph with "Normalized Average Height to Failure" based on "Incremental face drop on 180 grit sandpaper". Was it this test that they used for the derivation of the up to 80%?
Are hard, rough surfaces "180 grit sandpaper". What does "surviving" mean, are there no signs of damage? I would have assumed that you would have written "no signs of damage" rather than "surviving" as to me it sounds a lot better...
Additionally when tested was it just the glass dropped (I would assume so) or was it trying to represent a mobile phone drop and did it have a 150g weight attached to it? Without being supplied the test methodology I will have to assume the former.
Again if I look at the graph there is a hint that the thickness of the glass (perhaps unsurprisingly) has an impact on the numbers. So I am assuming that 80% is for the thicker end, which appears to be 0.8mm on the only supplied graph. Unfortunately I cannot find any dimensions, but the iFixit teardown of an S7 edge (GG4) looks like it is less than 0.8mm.
So given my assumptions above. If you have watched an S7 edge drop test you will have seen that from 1.6m the screen is damaged and often cracked. This is often from one drop. Based on the graph the general rate of failure to survive is 50% higher than GG4.
So in essence it looks like the chances of damage from a 1.6m drop on a Galaxy Note 7 will be close to 100%.
So yes you will need a case to avoid needing to buy a new screen.
Which leads me on to my next question. Why make the back of the phone out of glass rather than a far more durable plastic if you are putting a plastic case on it anyway?
Additionally why curve the screen rather than provide a lip to the edge to prevent the screen impacting the floor the majority of the time?