Ryan - I see what you mean. But I'd rather have broken ribs or even compound fractures and be aboard than to be merely bruised and wet yet watch my boat sail off without me (I usually sail alone). But it does lead me to sit back and think on whether a safety (i.e. backup) system should have a weak-link or maximum load specified. And also whether it should fail at the mount point or perhaps in the safety
line first.
On a related note - this type of shock loading is the reason that aircraft safety belts have a limited lifespan and new regulations stipulate that they also have a method to determine their highest g-loading. They, just like helmets, will absorb enormous amounts of energy in stretching just a little so that the ultimate load on the body & mount points is minimized. I seem to recall that my boat
harness attach points have similar webbing. And I also remember that it is time for a new 5-point belt in the plane.