You never heard of a thing called MINIATURIZATION?
Besides, it's the principle behind the articles, the workings - scale can be changed. Obviously you're not gonna use 30 or 20mm shells for a infantry-based gattling cannon, and thus the weapons itself would be smaller.
Note that you said gattling weapons don't fire in bursts - I proven that they can and do.
You then said that spin up time is too long - I shown you working ways it can be improved.
You mention the ammo issue - I've show you that there are ways to store and carry a bit more ammo (not much), but more importantly, that having lots of ammo isn't the most important thing in weapons. There are so many big, single use weapons out there.
So to conclude. Gattling based weapons aren't used by todays military as infantry weapons. (probably because the government won't waste $$$ on it when it can research laz0r weapons and invest in newer jets)
That doesn't mean that they can't be used, as the technology is more or less there.
Last, but not least, the game takes place quite some time in the future, and the last attempt at infantry-carrier gattling weapon was back in the 80's.
If you don't want such a weapon in the game, fine...but don't tell me it's impossible for such weapons to work if you haven't done your homework on the subject. Half the sci-fi plasma/particle/whatever weapons are more redicolous than that (specificely, why waste money and time trying to produce something like that when simpler technology works just as effectively; and secondly, a foot soldier's firepower will always be limited - after all, what's the point of heavy veichle support and urban fighting if you're single soldier cna nuke the city he's supposed to protect?)
I'm sorry but I spent 6 weeks in Germany in '89 hauling around an M249 and two ammo boxes on exercise, plus regular loadout webbing, helmet, and pack. It was heavy, and I was darned glad when that exercise was over and I could hand that weapon in. The M249 is a .223 calibre weapon, and it and its ammo are
still heavy. Those advocating a gatling gun, which together with its ammo would weigh at least hundreds of pounds, need to consider more than just miniturization. A minigun is designed to take advantage of a vehicle's cargo-carrying capacity to make a heavy-yield weapon. Maybe it can fire in bursts. Honestly, so what? Unless you eliminate ammo and make the gun impossibly light, it just can't happen. You need to understand the purpose of that kind of weapon. It's too big, and too heavy for ground soldiers. And anyone's who's lugged even an M-16 plus 6 mags around on exercise doesn't need to be convinced. Even a regular squad-level machine gun is heavy. The M60 and similar 7.62 machine guns were a major burden. Machine gunners usually need a second person to carry ammo. Even the .50 cal is basically a vehicle-mounted weapon. I never saw anyone carry one while I was in the army.
Consider also that a gatling gun's extremely high fire rate is intended to concentrate rounds on a hard target. You don't need to pump a hundred rounds into an enemy soldier, even if you could manage a one-second burst and get your rounds on target. Which you couldn't, because the recoil would knock you over. A hundred rounds on target is meant to destroy tanks, hard vehicles, and incoming missiles, as in the Phalanx Close-In-Weapons-System.
The soldiers in UFO:AI are commandos; they need to be mobile and move fast. They're not intended to engage super-heavy targets for which rotary cannons are deployed. Even if you could somehow make a rotary cannon that a soldier could carry, it would waste all its ammo on one target. Plus, how are you going to aim it? Rifles and handguns, even rocket/missile launchers are fired from the shoulder - a rotary cannon would be fired from the hip. And as anyone who's been on a real firing range knows from experience, firing from the hip is almost useless. Look at the Iraq footage - soldiers there run with their weapons at the shoulder-aimed position.
My opinion: keep the gatling gun out of the game, period. It doesn't belong, it's out of place, and it detracts from the focus of the game. UFO:AI excels as a proper squad-tactics game. A gatling gun, while fun I admit, would be ridiculous.