The only thing that makes this different than Yull Brown's original (look up Brown's Gas) patent is the lack of electric arc to increase the flame temperature.
The problem with this 'invention' is that it's just plain ol' electrolysis. The only difference in application is that instead of storing the gasses separately, the electrolysis chamber is designed to provide gas on demand, and already mixed together.
So yes, you can generate enough gas to supplement the internal combustion engine, but you cannot create enough on demand (yet) for running the car. I've read up on this before when videos of this gas first aired...this is commonly known as hydrogen supplementation... and it's done in various forms already.
The problem being, as with all electrolysis, is it takes more energy to extract the gases than you'll get from combusting them. So it's always a losing proposition (anyone notice the swing on that ammeter?)..
So most of the claims of it being revolutionary are a little overblown.
As far as using this to weld.. I dunno.. Too much oxygen is known to oxidize metals, and too much hydrogen is known to make metals brittle (someone correct me if I've remembered incorrectly).... So, even though hydrogen-oxygen torches have been around for a while, they've never been particularily well suited to metalworking.
As for the cool tip... any torch where you can keep the pressure of the gas high enough to keep the flame away from the tip will result in a low temp tip.
I think it's pretty telling of the american military that they've contracted out to this guy who's more showman than scientist... I'd hate to believe they'd be suckered into thinking their Humvees are going to run on water (in the desert ironically) because this guy could add a little extra hype to all the pre-established knowledge of water electrolysis.