I am probably over analyzing this but I am thinking of getting a SawStop before I retire so it is an interesting topic to me.
If the blade stops in .005 (5 milli seconds or less) as SawStop states, it makes sense to me that the injury will be a function of how far into the blade your body part moves in that amount of time.
How fast can we move our hands? One way of measuring this is to look at how fast a human can throw a baseball. 100 mph is not unusual for pitchers. I found claims of 150 mph hand speeds googling. At 100 mph, a hand would move 8.8 inches in .005 seconds. That seems to be obviously enough movement for there still to be an amputation. At 10 mph, your hand could move the width of your finger in .005 seconds.
We aren't winding up in a throwing motion in our shops, at least not when pushing things through the table saw blade. But if a board breaks or something and we are pushing that board, our hand could move pretty fast towards the blade. Seems credible to me I could still loose a digit with a SawStop saw. The OP illustrates it is possible to get a pretty nasty cut.
To me the bottom line here seems to be that we cannot count on a Saw Stop saw from preventing our injury. It will reduce the severity in all but the most extreme hand velocity situations, at least, but we still have to use good practices or we are going to need some stitches.
Saw Stop shows pictures of injuries on their website from people using their saws. But they are all the superficial hot dog type. That seems at least potentially dishonest to me. They have to know there have been others. If my math is right, stitches are not really all that unlikely. They admit in their FAQ that there could be a serious injury. If they know it has occurred and have access to the pictures, should they post them?
If the actual correct picture here is that Saw Stop saws are nice saws that add a measure of protection but do not prevent serious injury up to and including amputation, would everybody that has one have purchased it? Would most people still buy it?