Tanner is basically just a douche, kind of like some people think Chad is, but Chad isn't a douche, Chad is really funny and is just a genuine savage. Everyone loves Chad, even if it's just begrudgingly, unless they're insane and want to kill Chad out of envy. Okay back to Tanner. No one thinks Tanner is actually that funny. If they are laughing at his joke, it's because they overestimate his social clout and want to be adjacent to him to increase their own shit-tier standing. He isn't really popular, but he IS capable of making friends who aren't autistic and who do not interact with him initially only from things like dungeons and dragons.
Tanners can often be mistaken for Melvins, or a really, really third-rate Chad, but only by people who don't understand or at least recognize the many nuanced layers Chad operates on so effortlessly. (Sidenote: Chads don't necessarily have to understand their own behaviours completely in order to continue them or to be a Chad). Tanners also confuse people this way because they readily offer up their own resources, for example a Tanner will volunteer his parents' house for a high school party. In this scenario, Tanner hasn't actually brought anything to the table himself, especially not with his social skills (because they are poor - unlike Melvin's which don't exist at all). Tanner is attempting to buy social clout, likely thinking he can get laid with this method. He might, but he will not retain a truly valuable lady, an elusive Stacy, if he is even lucky enough to snag one for that fateful night. Many people besides Stacys and Chads will mistakenly believe having hard resources can make you a Chad. Chad is both a status, and a mindset, first and foremost. Hard resources are simply something that comes to Chads from their hard work ethic.
Tanners often do possess enough cleverness to recognize Chads. Tanners, because they are not completely oblivious to the repercussions of their mistakes like so many Melvins are, universally fear Chads. To be fair, it doesn't take a ton of cleverness to recognize Chad. Some Melvins can do it. The main motive for Tanners to identify Chads is to attempt to be adjacent to them, to swim in their wake so to speak. This nearly always ends poorly for them, because Chads can coexist with each other when in environments with plentiful Stacys, and with Chads in the picture, Tanner is basically invisible. Tanner will almost always end up with a Margaret in this scenario, but generally avoids Gertrudes as they think themselves too high ranking to stoop to Gertrude.
Through many years of efforts, poor quality as they are, Tanners can eventually develop a reasonable enough understanding of the power dynamics that surround them, if they didn't have that earlier in life. For this reason Tanners will attempt to occupy spaces that are vacant of Chads, to assume Chad's role and hope to fool those in that space. Stacys tend to instinctively know something is wrong, but while experiencing Chad-scarcity they find a way to rationalize temporarily stooping to a Tanner, especially if he or his parents have money.
Because Tanners do not possess the natural social skills, chiselled forms and sexual abilities that Chad does, it's only a matter of time before he slips up and Tanner's tactic of pretending to be a Chad blows up in his face. Tanner will likely go through a period of hard Melvining after the devastation of his one-sided bonding with a Stacy and then losing her.
Chad has total social dominance, and even if he's borderline retarded, he at least vaguely knows it. Margarets who cannot retain Chads and are aware of it may pretend to not be into Chads, and may seek out Tanners to try and pussy-whip into trophy boyfriends to present as a Chad, that may fool other, less experienced Margarets and Gertrudes. Stacys will always figure out Tanner isn't Chad in the end though, but then again Stacy doesn't like lowering herself to hang out much with Margaret and Gertrude in the first place.
Although inconsequential, Tanners may be identified by Chads as non-Melvins, but also as non-Chads. That's why it's inconsequential. Chads treat Tanners as Melvins because relatively speaking, with Chad around, they are. Tanners are generally competent enough to get degrees and decent jobs, though it isn't a guarantee for them. It isn't a guarantee for anyone. However this remains a requirement for any non-Chad to retain even the lowest level Margarets and Gertrudes. Again, going back to hard resources, they are most often a substitute for charm, tact, good looks, height, athleticism, sexual prowess, and humor, in this context. Only the inexperienced will fail to recognize this in "the dating market" free for all.
Tanners also confuse people because they can have, or mimic; popular fashion style, sense of humor, and entertainment media choices. They also may attempt a gym routine, but are often not dedicated enough to make substantial "gainz". Although at first glance a Tanner's style may seem on point, with careful scrutiny it becomes obvious Tanner is a try-hard. Chad wears whatever he feels like. Sometimes he puts literally zero thought into how he presents himself. Tanner never does this. Tanner is always self conscious. He also knows very little about the entertainment media he is careful to always present himself with. This is another dead giveaway of his real identity. Tanners also may have a witty remark to make in the ideal situation, if they speak up first, but it should be noted that it's usually memorized (mimicked from experience with Chad) and practised, and that their utter lack of natural improvisational skills will rear its ugly head fairly quickly in an evening of light hearted socialization, leading Tanner to lose the attention of countless Stacys.
Keep an eye out for the subtle indicators of a Tanner, and observe them in the delicate ecosystem that is human group interaction. It will be on the mid-term.