Ok, ... here is were the confusion is, ...
The article said he had POOLS of brake cleaner, and he welded over it. First off if he saw the POOLS, ... why did he weld over them, ... Also this guy is short of a few marbles as he was trying to dry a flammable liquid with a torch. Something tells me Darwin has had this guy on his list for some time now.
The way I use it is not by spraying it directly on the the steel, ... You spray it into a rag and then you rub the rag on the steel. The stuff evaporates so fast, ... you have to keep respraying your rag every 10 seconds on average. I have done this for over 30 years WITHOUT one incident of any kind. I prefer Acetone, ... but if I'm in a pinch, ... out comes the brakleen.
As with any product such as the example already given, A knife, ... yes you can kill yourself with it if you are irresponsible with it's use, ... but then so is a marshmallow if you don't chew it before you swallow. Just about everything you use in life can and will kill you if you let it.
Respect and responsibility for the use of any product no matter what it is, is a life or death matter. So with the information you have read in the article, ... use common sense.