I too, along with Romania was taught this technique. In my case that was around 15+ years ago, so it is not new in the US. It is one more tool in the arsenal, and if you think about the discussion regarding defensive vs. offensive tactics, this is more offensive in nature.

As to gas removal, it has been a tactic for quite some time to ventilate roofs to allow the hot gases and uncombusted particulates to be removed from a structure. The use of positive pressure fans/ventilation or spraying a wide pattern across an open window to create a Venturie (spelling may be off) effect have also been useful tools in the arsenal to remove smoke and hot gases.

With that said, keep in mind that a significant portion of the personal in the US Fire Service are volunteers, some with equal training and experience to their career counterparts, many with less. There has been great strides in Firefighting education and training, but in many areas, much still needs to be accomplished.

Pete