That’s kinda the message of the last paragraph.

I grew up playing in the late 70s/early 80s, and honestly I didn’t give Gygax a second thought. He was pretty well known to be a coked-up crazy coot, and most of the really interesting AD&D materials weren’t made by him anyway. By the late 80s he was mostly out of the picture.

It’s a common high school chem lab demonstration. Without added oxygen, the H2 balloons sort of burn from the outside in, and you get a sort of slow burning mushroom plume. It could light paper or cloth on fire in close proximity.

With added oxygen… BLAM! It could shatter windows.