I run Snakeskin on various bikes. Three experiences that might help. After a rocky ride I checked and found a deep score mark on the sidewall of the front tyre on my Cotic. It looked like it had hit a rock or whatever. The score mark went as far as the inner casing, but that has held since. I am certain that that would have been a complete tear on a non-snakeskin tyre.
I noticed a bit of white on the rear of my susser. On checking I saw it was a 1mm hole that has sealed with Stans. Closer examination found a further dozen similar sized holes in the same tyre, all in or around the tread area. I can't pin it down to any one particular ride, so in the last twelve months or so that bike would have punctured a dozen times but has sealed itself quite nicely. Again, 2.4 nic Snakeskin.
In the last month or so I have ridden Penmachno, Marin, Kirroughtree, Mabie, Marple, Calderdale, and Kirklees, all of which have had their fair share of rocky nonsense, and the tyres have survived my lack of ability and 15.5 stone.
Finally, my lad charged a square edged step at Clayton Val;e and managed to pinchflat his Snakeskin rear, so if you are a 15 year old blunderer it is possible to smack them hard enough to knacker them. I ended up having to patch that one from the inside.