On PC the BFG, Rocket Launcher and Grenade explosions cast dynamic lights, but the muzzleflashes are still absent. I haven't double-checked monster projectiles (Imp, HK, etc).
Checked BFG on 360, same as you described above + fireballs of enemies that cast lights.
There we go that's what I've been trying to get at. Remember I said "I can't understand for the life of me understand why Tim Willits didn't design Doom 3 to be a scary game.", all the flashlight did for some accidently added a dynamic to the game that changed it from a fragfest to a more immersive scary game. Remember though that wasn't the point of the flashlight.
, because Doom 3 was supposed to be a fragfest with a small story. I disagree with Tim's choice to make a fragfest rather than a scary game, so I'm not backing him up there, just trying to get you to look at it from the designers perspective.

This is what i don't understand. I never considered the Doom3 of 2004 to be a fragfest.
It always was a scary game no matter how they originally intended it to be.
I have friends that stopped playing halfway through the story because they thought it was too scary!
Especially ROE had some very intense surreal and nightmarish moments in the original.
With the changes made to the BFG edition, it looks like Tim Willits "corrected" the gameplay to what he originally had planned.
I'm exaggerating now to make the point clear:
The original was a great and unique scary experience, the BFG release is a mediocre shooter.
Doom3 2004 was well balanced. The BFG edition has lost it's character.
The enhanced gameplay speed is welcome though.
I always thought the player movement in the original was too slow.
Dodging imp fireballs is easier now.
It doesn't matter what it was supposed to be, only what it was truly matters.
You shouldn't change an 8 year old "classic" after all the fans have come to love the original.