There's much to be said about black outs, most of it has already been said. I stick to the float and line method, but on top and most important of all is the buddy diving , which doesn't mean you gat sepparated. Buddy diving in depths means , two guys , one float one line ONE GUN. If there's a second gun it stays attached to the float fot the case it's needed. Asong as i'm concerned there'll never be acurate buddy diving if both have a gun and a lot of eagerness to shoot a fish.
Good points Pantoja. Unfortunately, in reality, we all dive with guns in the hopes of that dream wahoo.