so it could be that gen will include UFOs in the game

Actually, there are documented accounts of men hefting belt-fed machineguns on foot in battle.  Guys did it with the M-60 "pig" in 'Nam, the M-249 SAW is routinely carried by the USMC for rear guard position on Chinooks, but the best situation I know of was a night situation during WWII where a guy had set up water-cooled machinegun posts to defend an airfield on an island the US had captured but had not fully secured.  He and his troops at a forward position took down a bunch of enemy soldiers when they tried to sneak up on the base, using a simple tin-can tripwire alarm.  He had to ferry ammo back and forth to the other gun positions since there were more troops incoming than they had expected, and when he went back to his gun to reload it he nearly got his head blown off by a Japanese soldier who set up a namboo machinegun before he could re-arm his own weapon.  Well the Japanese soldier's burst missed him by a few inches, and he nailed the other guy after getting his gun un-jammed.  He then PICKED UP THE GUN and carried the thing on foot, mowing down the enemy squad that had slipped past by following them with the gun in-hand.  A water-cooled Browning machinegun is a heavy SOB, 41 lbs and that's without the ammo, and had never been used like this before.  Here's a picture of one:

http://www.1919a4.com/manuals/images/RAPD4164.jpg

The defunct minigun variant XM241 weighed around 33 lbs without ammo, and that's INCLUDING the motor and battery.  A recoil or gas-operated gatling gun would be a quite a bit lighter than that, so with ammo it would be entirely possible to carry for a REALLY strong guy.  Now carrying TWO gatling guns... well, I can see where Blaze might be able to, but Mynx?  Well, this IS a game, after all!  Besides, where does Grunt hide all 10 of his guns anyway?  I think "realism" elements should be viewed like this.  If adding an amount of realism improves the gameplay, adds a unique quality to something, or in some-way the general fun, then go for it.  If it's an impediment and spoils things, then why wreck the game with it?

GK: you also forgot Cacodemons, Pain Elementals, Tar Babies and those Flying Hitlers from Spear of Destiny... tsk tsk

Edit: And also the Boss creature thing from the Q2 Big Gun episode

Miniguns and gatling guns are the same exact thing (unless you're talking in old times, where the gatling gun were actually cranked by hand...)... both have rotating barrels and are belt-fed. No such thing as a clip loaded mini/gatling gun. The actual term for them is a Vulcan, but no one seems to call them that any more. Now miniguns and chainguns are actually different. Chainguns really only use 1 barrel to shoot from, but whatever.

Besides, it's not like the gats were realistic back in Wolfenstein without the laser sites since they weren't used in WW2. I don't care whether the lasers on the gats are realistic or not. I just think they look kinda dumb, particularly since they just extend about a foot, then misteriously disapear. They don't look like laser sites, they look like folding radio antenea or something that someone painted red. Laser sites don't actually make red beams shoot out anyway, they just project a red dot on the wall, unless there's fog or something for the beam to reflect off of, not that it's a realism issue, it's more of a simple logic issue. Also, since the gats are one of the earth weapons that actually was in Wolf, as opposed to the mortar or sniper rifle, logic would have it that they look like the guns from Wolf. IMO, the laser on the Q3 shotgun was dumb, but continueing that idea (espccially in the first person view of the weapon) is worst. I don't mean to be flaming Tabun or anything here, I'm just talking personal aesthetics.