This is a call to those of you who have some experience on which to draw. OK, depending on your outlook and training, and assuming you are diving or were diving OC, sometime in your past you considered the various failure points of a set of manifolded doubles. You may also have drilled specific reactions based on the type of failure and so on. One may breakdown the potential failures into those behind your head (nine "options" according to some... many fixable most not) and those in front (hoses fixable, hoses unfixable, second stage issues, SPG, LP issues et al). Anyhow, here's my question... while researching for a book I'm finding very little data for actual instances for real behind the head failures. And among those few actual incidents... I've had burst disks go about 100 metres up the Peanut Tunnel... none were fixable. My feeling is that fixable issues SHOULD BE caught before diving by pre-dive equipment checks (loose hoses for example). How about you folks... what's your actual experience?