Yea, that's some impressive shooting. However, to do something impressive doesn't even require the fastest shooters in the world. I knew a guy who could draw and fire 5 accurate rounds to knock over 5 steel plates at about 10 meters in under 3 seconds. I saw him do it multiple times, in fact. I could never beat him, but even myself, after shooting handguns for just over a year, could do the same course of fire in 5 seconds (at my absolute best, that is). I started that year off sometimes doing the same course of fire in over 50 seconds, so improvement was rapid.
However, that's in an enclosed target range, with nobody shooting back at you (although the competition was head-to-head, each person with his own rack of 5 plates, so it was somewhat intense anyway). I used a Glock 19 and we limited ourselves to 6 rounds per magazine so revolvers could be competitive. With a reload, I was probably still in the sub-10 second range, meaning I could fire 12 shots with a reload in under 2 rounds. That simply can't be done in most RPGs, let alone Traveller.
However, I think it CAN be simulated, more or less fairly. First, you simply have to remember to give LOTS of +DMs for ideal conditions. I'd also call this kind of "trick" competition shooting something decidedly different than combat--maybe call it an opposed Gun Combat check even.
At any rate, I've never tried too seriously to allow players in games to fire that fast with any accuracy in a combat situation. That said, it can sometimes get frustrating when, in reality, a battle could be over in 6 seconds with many shots fired. Not really sure what to do about it.
The ONLY game that is remotely realistic is GURPS, which allows 3 shots per round, and 1 round is 1 second.
Oh, and for the record, since someone was talking about off-hand shooting, any shooter with his salt WILL TRAIN off-hand. ESPECIALLY if you take any of the numerous defensive shooting classes offered around the country (USA obviously). My dad's taken many courses and in several, they even practice shooting with the off-hand while laying on the floor, as if you'd been knocked over. Off-hand training is also common in IDPA (international defensive pistol association) matches, where the purpose is to simulate defensive shooting situations.
So, if the question is whether military and police train using the off-hand, the answer is a resounding YES barring negligent management.
(Plus, it's not that hard. We would sometimes switch it up and do off-hand, one-handed challenges with the plates. I could do it in about 12 seconds with my off-hand, one handed. Granted, I was better at it that many, but with a bit of practice, it's not that tough.)