This page is for all guesses involving the Red Team of Red vs. Blue.
But Sarge seems to be a different case altogether: not only does he lack similar flaws, but he's extremely skilled at constructing and maintaining robotics, vehicles and the like (even demonstrating a medical knowledge far surpassing Doc when he rebuilt Simmons and Grif), he's proven to be a consistently skilled soldier, and a solid (though not always logically sound) tactician. He's even had moments of extremely advanced critical and analytical thinking (such as the time he deduced the situation at Valhalla based on minor details of Simmons' correspondence). He proved skilled enough in fact, that it was mentioned that he used to be an ODST.
My theory is that during his time as a helljumper, Sarge experienced some sort of traumatic event that resulted in an extreme form of PTSD which resulted in his lucid, yet...let's say "unique" interpretation of reality. Rather than discharge him completely, he was then snatched up by Project Freelancer and given command of a squad at Blood Gulch with the hopes that his expertise would be an asset in the defense of the installation should a hostile force ever discover the whereabouts of Alpha (with Butch Flowers/Agent Florida there of course to provide around-the-clock protection in the [extremely unlikely] event that one or several of the sim troops posed a threat to the alpha). His compliance in this endeavour would have been relatively simple given his initially unwavering faith in the orders and judgement passed down by "Red Command".
If you don't mind taking a few leaps of faith (pun intended) with the narrative, you could arrive at the conclusion that perhaps Sarge served with and/or commanded a disobedient, lazy Helljumper at some point in his career (or maybe even Sarge himself screwed something up). Said hypothetical ODST may have then possibly caused a mission to go badly sideways through their failure to properly prepare, maybe even costing one or more squadmates their lives. Fast forward to Blood Gulch, and the sheer degree to which Sarge hates Grif becomes a lot less funny. If you accept this theory, then Sarge isn't just a trigger-happy General Ripper sort. He's a man whose post-traumatic stress flareups occasionally lead to him violently attacking a subordinate he may well see as a stand-in for someone who made a mistake years ago.
- I think this is more or less canon..."You have a fear of heights? Didn't you used to jump out of high orbit during the war?"
"And how do you think I got that fear? That @#%$ was crazy!"
- Alternatively, Donut has been promoted beyond Sarge's command because of his l33t grenade-tossing skillz.
- It appears that Donut received a promotion in the same vein as Tucker, only it was based on his ability to appear anywhere, unexplained, rather than combat ability. He states that he's become an infiltration specialist in several deleted scenes, which appear to be canon. Insert Innuendo Here.
- He's a deep insertion specialist behind enemy lines. Hey, you asked for innuendos!
- But Sarge kills people successfully. Not Grif, mind you...
- Who says Peppy hasn't killed anyone? He participated in a war consisting of four paper airplanes against over 150 spacecraft per planet, including (but not limited to) Flying Saucers, Humongous Mecha, the Temple of Doom's Evil-er Twin, Nuclear Missiles, Imperial Star Destroyers, and THEIR OWN GOD-DAMNED SUN. Either Venom's forces really suck or the team is just that badass. And Grif is probably being kept alive so he can be harvested for spare organs... or is just the local punching bag.
- That actually makes a lot of sense. He has been stated to be "crafty" on several occasions, and this approach would certainly count, as well as allowing him to avoid actual combat.
- Crafty by Church's standards. And while Church is the Only Sane Man, he's not a bright Only Sane Man.
- Highly unlikely. When Sarge discovers the dead Blues, the Symbol of the Meta is carved into a nearby wall. Caboose, Grif and Simmons were relocated into the same location ("You were at Rats Nest too?"), Washington picked up Caboose earlier and the Meta was following Wash at that time. So, the Meta killed the Blues, the Reds just didn´t notice.