It's far easier to do than most people think, many people are figuring out how to do it on their own. Someone in the spanish community figured it out and is now teaching almost all of the rest. If it's not already at a point to be considered an "epidemic", it will be fairly soon.
Advantages:
- No visible weapon to obstruct your view
- When you reload, you do the limbo. If you're not moving, you lie down completely (That's a video from when Grand Master Kubo discovered how to do it with his ion pistol and nova knives and starting teaching people how to do it. Though he never figured out how do it with other weapons reliably). Yes, it does move your hitbox with your body. I've lied down on the ground in front of a proto maddy many times and avoided receiving damage.
- In some cases it "silences" your weapon. Though most often it just replaces the sound with whatever it looks like you're holding.
- When done with a non-projectile weapon, no bullet streams. This works especially well with the laser rifle, it gets rid of the visible beam and the loud laser sound.
- Jedi mind manipulation, your opponent will react to you as if you were holding something that can't deck them from 70m out. They learn the truth pretty quickly though.
People call it the "Limbo Glitch" but the limbo is just a by product of what it really is. It doesn't just work with the Rail Rifle and nova knife,
you can mask any item you're holding with anything else.
In that video someone else managed to do it with their ARR/bolt pistol. It doesn't produce the limbo, but it sure sounds and looks strange.
I've tested pretty much everything, one of my favorites is the HMG and sniper rifle combo on an Archduke's. It shows you holding a sniper rifle to other people, but to you it looks like you're holding an invisible HMG. When you fire it, to other people it looks like you're firing a sniper rifle as fast as an HMG, and dishing out the damage of an HMG. Firing sound, bullet streams, all of it. Pretty intimidating.
The one of the differences is its easier to do it with charge up weapons, and the limbo only works with Nova knives, nanite injectors, repair tools, and scanners. The nanite injectors are interesting because they produce the "revive" animation when you fire a low ROF weapon like a PLC or Breach shotgun, while producing the limbo when you're reloading. Oh, thats another thing.
The limbo only happens while you're reloading. Certain weapons take advantage of this better than others, like the shotgun. It can interrupt its reload animation with a shotgun blast rather than sprinting or switching weapons. I can't recall another weapon with that ability, it enables a breach shotgunner to do the revive animation of the nanite injector immediately followed by the limbo with very little time spent standing straight up.
For someone who knows what they're doing, it's a significantly advantageous, though all of the advantages are visual/audio. (except the limbo/hitbox part)