How to reconcile the 'no talking' artistic device with the actual plot
In Half-Life 2 Alyx mentions that she was told Gordon "was a man of few words." Obviously, then, all those times Gordon was silent weren't necessarily just because you were supposed to imagine yourself speaking through him--he actually didn't talk.
Therefore, why has no one considered the idea that Gordon is a mute? I see no reason why not. Perhaps this was the joke behind the "Black Mesa is an equal opportunity employer" part of the announcement during the opening tram sequence. The fact that there were no females in Black Mesa (except for Gina Cross, of whom I'm not sure is canon), was just one part of the joke--the other half was that what they actually meant by "equal opportunity" referred to the fact that they would hire disabled persons, e.g. Gordon, who was a mute.
If he was a mute, then what do we make of Alyx's statement? Well, perhaps she simply misinterpreted an ironic comment someone told her and took it literally. Maybe--as she obviously has a crush on him--she misspoke and said something stupid because she was so nervous.
If so, then why didn't he use sign language in the first game? Well, the real reason why Gordon never got a voice or any lines is because they couldn't figure out what he should say or what his voice should sound like in time for the launch date, so they simply omitted these things and hoped no one would notice. Only after they realized that what they did was a huge success did they capitalize on this new form of storytelling. (I think they go over this in Half-Life 2: Raising the Bar...it's quite unfortunate that I put it in storage and can't be bothered to dig it out). However, plot-wise, I think Marc Laidlaw retooled it to incorporate Gordon's muteness. Ever notice how characters speak at him, not with him? If the players were truly supposed to be having conducting conversation with their lines being "insert desired line here," then the NPCs would pretend you said something in their conversations, which they don't. They simply give you instructions or explanations...any new progression of thought is controlled by them; any new idea comes from "realizations" during their speech rather than from any input from Gordon.
Perhaps he wasn't supposed to be mute, then, but rather, the "strong, silent type" taken to extremes. He simply communicated through his sheer force of personality as expressed via his face and body language. (The only similar character I can think of off the top of my head would be "Sphinx" from the remake of Gone in Sixty Seconds, who only deigns to speak at the end of the movie...if the Half-Life franchise ever ended, having Gordon say something as well would be pretty cool, wouldn't you think?).
Just look at how he is portrayed in the game art: he's always in combat or looking like a badass. In the HL1 manual it states that his first invention was a butane powered tennis ball cannon (I believe he built it at 8, so he displayed these characteristics since he was young); the only character who seems to have an affinity for Gordon in the Anomalous Materials lab is Barney, a character whose job description is to "kill things and break stuff" when the time calls for it. In Episode One, he also says "Now that's the Gordon Freeman I know!" after you blow up a Combine APC in such a way that he wasn't referring to Freeman the Legendary Resistance Fighter aka The One Free Man, but rather, Gordon Freeman, the Guy he Knew From the Anomalous Materials Laboratories (i.e. the scientist who was unusually badass)...after all, how could he have witnessed Freeman in combat at Black Mesa when all the security guards you use after The Incident are simply Barney NPCs and not the Barney character himself, so he couldn't have witnessed you in combat firsthand?
It's clear that the only people Freeman hung out with were security guards, as he even seemed to be their drinking buddy, hence the "Catch me later, I'll buy you a beer!" line. When Barney says "Now, about that beer I owed you..." in HL2, it isn't just a nice reference to HL1, it's also said in such way that suggests that they were good friends even before The Incident. (Frankly, however, I can't really figure out who Barney's supposed to be. The Barneys in the Anomalous Materials labs were the ones who owed him the beer, while the Barney from Blue Shift [the one that escaped with Kleiner and whom you see in City 17] was the Barney trying to open the security door near the beginning of the opening tram sequence. In any case, however, it's pretty clear that he would only offer a beer to people he got along with--could you really imagine Barney having a few with the pole-up-the-butt scientists from Black Mesa?).
It's also fairly evident that the other scientists' disdain for or arrogance to Freeman went beyond the traditional "razz the new guy" attitude common to most workplaces. Could it have to do with the fact that Freeman got the job because Kleiner was his old professor at MIT and therefore didn't have to interview? Perhaps. But it also seemed as if they were the stereotypical academics: They saw the "alpha male" Gordon, who caused them in turn to reflect upon their lack of masculinity. This angered them, so they decided to assert their dominance over him by being condescending toward him. The fact that he was a genius and therefore couldn't be out of his depth when it came to science like Barney probably only made things worse, as that meant the only advantage they had left over Freeman was their seniority--hence the reason why Freeman was stuck with the HEV with no helmet. Also, remember the way the line "They're waiting for you, Gordon--in the test chamber" was delivered? Maybe the hint of malice intoned there wasn't just irritation at him being late, it was jealousy that Freeman was the only one courageous enough to brave the barrel; after all, it seemed as if Freeman was consistently stuck with slotting specimens into the device.
Oh and don't forget the fact that when you get the Egon, the scientist who invented it wrestles with the moral implications of using it on life while Gordon has no trouble accepting the gift.
If the cover to the Game of the Year Edition doesn't say it all, I don't know what will: http://upload.wikimedia.org/wikipedia/en/f/fa/Half-Life_Cover_Art.jpg
Maybe we interpreted Gordon wrong all along. Perhaps Laidlaw was going for something different here--he wasn't a mild-mannered scientist, who, with the aid of his HEV, learned to handle himself in combat; on the contrary, he was a mix between John McClane and the strong, silent type who wasn't averse to violence, liked to drink with security guards, show up late to work because of his hangovers, and just happened to be a genius. Hell, I bet they would have drawn that picture with a cigarette hanging out the corner of his mouth if the tobacco lawsuits weren't so controversial at the time!
This could be what Laidlaw was trying to say with the Adrian Shephard character: He doesn't speak and handles himself quite well in combat, even for a Marine, just like Gordon. After all, if great minds think alike, why couldn't great warriors act alike? He is peas in a pod with Gordon; they would get along fine...Gordon is a fighter in scientist's clothing. Just look at what is implied in this portrait: http://upload.wikimedia.org/wikipedia/en/a/a9/Half-Life_Opposing_Force _box.jpg...the eyes are similar, the stance is similar, even the proportions are similar...they are similar souls who walked different paths.
Sorry if this seems to be a bit disorganized; I originally just wanted to talk about how Gordon could be a mute and it kind of got away from me. I also realize that I may be inferring too much into things and may be stretching my points but I still think it's possible since the Half-Life story was deliberately told in such a way that players have to arrive at their own interpretations by piecing together different clues as to what Laidlaw was trying to say.
P.S. Does it bother anyone else that they took this approach to Barney in Blue Shift? He wasn't supposed to be a player-defined character, he was already an established character in his own right who was supposed to be quite a wisecrack, so he should have said something, correct? Perhaps he was supposed to be so disgusted with the scientists that he had nothing to say to them. After all, in the original Half-Life there's a sequence where a Barney gets pissed off at a scientist and exclaims, "This [i.e. The Incident] wouldn't be happening if it wasn't for you scientists!"
P.P.S. Going back to the mute idea, many people have speculated that G-Man isn't an alien, but rather, Gordon from the future. If so, is it possible that he speaks so strangely because he had his voicebox replaced? And why doesn't he hiss his Ss anymore like he did in HL1?
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