The cool Guys of GW have randomnized the Crush-Depths somewhat!
If you go deeper you'll get crushed for sure!
As for the deal! If a Boot was in a good shape, it could good deeper than assumed and survive.
The more stressed the pressure Body was before the more likely to get crushed early!
In the end none know the ultimate stress test. There are only a few who made it deep enough to know...but they stayed there!