As with
KLGunner, I also think that the muzzle flash was likely washed-out for the camera by the output of the lights as well as the backdrop behind the shooters.
The other possibility is that the ammo used was a good match for the guns, and allowed production of less muzzle flash.
I know most of y'all have seen this picture of mine before:
View attachment 2629
^ That night, I was shooting Remington UMC bulk, 115 gr. range-fodder. It's super-flashy (looks kinda like I was shooing a tracer!) in my little XDm9 3.8 Compact, but you know what? I actually
didn't notice this from behind the gun.....
@KLGunner , be careful when you're practicing, especially if you go alone. Part of the reason that the technique presented in the video (the "FBI technique") is used is that it is virtually impossible for the shooter to self-wound the support/light hand when using this technique (the sidebar about someone shooting the light? if you have enough light, your opponent will simply be shooting in the general direction of the light, so how high or off to the side you're holding the light is rather irrelevant). If you want to practice various hands-together techniques, take the time to sequence/choreograph your movements so that the gun is never brought up in a way which will sweep the support/light hand.
Also, in terms of available on-line resources, low-light videos on the Surefire YouTube Channel under their "Field Notes" as well as Aaron Cowan's Sage Dynamics YouTube Channel are well worth your time. Similarly, search on Google for the following terms: "strategies of low light engagements" and look for a .pdf hosted by someone with the screen name of "Galdalf23."
Download that file. Its the old Strategoes International hadgun low-light syllabus by Ken J. Good, and despite its years, still serves as an excellent primer.