Well from a vague test I can conclude that his findings on the foregrip/muzzle break are total [censored] if you're playing console, or PS3 at least.
I grabbed the following Gerund set-ups, jumped into Escort Duty, stood in a corner, aimed at the exact same mark on the wall and fired off the entire clip. I then mentally took note of where the sight was by the end of it.
- YeoTek RDS
- YeoTek RDS, Muzzle Break
- YeoTek RDS, Foregrip
- YeoTek RDS, Muzzle Break, Foregrip
The bog-standard RDS setup leapt a HUGE distance, whereas the RDS/MB/grip combo barely moved half as far up the wall... we're talking about 1
1/2 meter difference between the two at about 5 meters from the wall. The Foregrip and the Muzzle Break setups were also relatively identical. I also tried it with a Galactic SMG first, since he said that's the only weapon the Foregrip works on, and there was also a noticeable difference to the stability when stacking it with a Muzzle Break too. I also noticed that with the Gerund and it's 3 magazines, the first magazine had a lot more recoil than the other two whereas the last magazine had the least recoil... when all fired one after the other. Not sure what that means.
Basically, PC version might have strange coding or whatever, but I KNOW what I saw when I tested it on PS3. Try it yourself, there is certainly a very large difference when firing the entire mag on full-auto... not that you ever should, but it shows that going for extra stability will make smaller bursts all the more stable.
OH, and I also noticed that when using a COGA scope on the Gerund and firing 3-shot-bursts, though the gun doesn't recoil the scope will shake. Equipping a foregrip/MB reduces the severity of the scope's shaking too.