Let's just put it this way. The autoignition temperature of propane is something around 450C (840F). At normal pressures and at that temperature, water vapor, one of the byproducts of propane combustion, is spread into the surrounding atmosphere at such a high rate it's local presence is practically nil.
That's why you get asked about condensation. If there was a lot of water in one place, there would be evidence. There is no evidence, hence there's not much local water. QED.
I seriously doubt you have enough plasma physics for me to get much deeper than that. I know I don't, and I'm pretty sure I've got a lot more than you.
Furthermore, you're using language very loosely when you talk about "direct" heat, and I shouldn't have humored you by accepting the convention in my last post. All broiling is done with one sort of "direct" heat or another -- whether contact or radiant. In cooking, the only "indirect" is convection. In contact, radiant, and convection are the big three when it comes to heat-energy transference for cooking.
Most "direct" gas cooking is some sort of radiant. You can look up "char grills," gas fired IRs, "flavor bars," and other systems to see a variety of ways in which natural gas or propane are used to produce radiant heat.
Typical gas grills don't use the radiance from the flame only, while typical broilers do. Most grills heat some sort of intermediary material such as a ceramic briquette, a "flavor bar," a ceramic infra red plate, etc., to produce a percentage of the radiation for energy transference. On the other hand, gas broilers usually just expose the meat to the radiation produced by the gas itself, by putting the meat below the burner. Modern IR broilers are similar to grills, but with the ceramic element mounted above the meat.
Same amount of gas being burned, sometimes more -- but no moisture.
The Hasty Bake uses a combination of radiant (from the metal between the charcoal and the meat) and convection to cook. The purpose of the Hasty Bake design is to prevent flare ups. The idea is that the charcoal scent gets to the meat even though it's not directly exposed to the coals.
Last, perhaps I misunderstand the situation, but I don't feel any obligation to teach you enough about physics, chemistry and cooking to correct all of the misinformation in your original post. That doesn't make you right, it just makes me lazy.