I think it's kinda hit or miss. Some people pass out right away and die, others can't even feel like their about to pass out or pull themselves up the very moment their survival kicks in. It doesn't seem very reliable.
I wanted to use that method but after reading so many posts about people failing it, I'm going with full suspension.
But even people who try full suspension fail, they pull themselves back up somehow or get "saved"... Man, I wish people who succeed could post on this forum cause sometimes I lose faith.