For information on gaseous explosives you need to turn to military sources rather than the IME. There isn't much of a commercial market for Fuel/air explosives.

The terms "high order" and "low order" have been in use for a lot longer than 50 years among untutored blasters. "Low order" has been used to describe:

Too little explosive

Incomplete detonation

Lack of damage to adjacent hard targets

Deflagration

LVD

Any weak explosion

The alleged effects of a low explosive

The two terms have generated a lot of confusion over the years because of the inevitable tendency to try to correlate them with "low explosive" and "High explosive." The same thing will happen in FI.

Adopting murky idioms from the fringes of other sciences and sanctifying them by enshrinement in 921 is not a good idea.

It is also not a good idea to cite your own writings as learned sources. The reasoning gets a bit circular when you do so.

Again, I suggest that in some future edition of 921, you ditch the imported slang terms.