(also) apparently using laser sight is a must for all weapons.

...and the logic behind this is a really simple one:

Lower cone of fire = CoF tightens faster while ADS'ing.

And the "long short story" behind this is that I saw this video, went for the same "I'm gonna try to mimick this" shenanigans and it worked. Hell, I even managed to down those typical "chain headshotting me like theres a magnet on top of my nose" players. And yes, more than once, even while completely rusty (It's my second day back in the game after a long hiatus.). Also had a couple situations where I died, but made the heavy wipe both of his shield ability and its "basic" shield (Not a normal occurrence before then, but right now it is.)