It's a good glitch, but it doesn't work as good on the Xbox as PC from what i've heard and experienced. It's easy to get it to multiply a few times, but rather than a "rhythm" to it, it feels rather random to me. I can chain it dozens of times in a row and then switch to the weapon and have it reset to normal shots.
What the youtube doesn't tell you though is, is that you can replace the weapon you have upped with the glitch and have it keep the stats, heck you can even replace the Evil Smasher once the glitch has taken effect, essentially giving you two glitched weapons.
For some reason it's hard to get to work with the Fibber or Harold, so it's best to do it with other weapons and then switch these in after.
Also, you can keep all 4 weapon slots in use since you can just use the d-pad to back and forth select weapons which to be honest does the glitch just as good since it doesn't work right on Xbox. Of course this is my opinion, someone else may have better help and tactics I am unaware of.
GAMERTAG: Casperstar X "For those of you wondering whether the above made sense, you've just answered your own question."