Seems like we have a few different concepts floating around at cross-purposes here. Let's see if we can untangle them a bit ...
1) MMA is made up by people. So is every other martial art on the face of the planet. If you are allergic to the term "made up" for some reason, you can say "invented" or "developed" or even "discovered." One way or the other, they are all the result of human creativity.
2) "Made up" doesn't mean "something pulled out of the inventors brain with no connection to anything that came before." The people who invent/make up/develop/discover a new style or a new technique are doing it based on and in the context of whatever training and other experiences they may have had previously. This is no different from any other creative endeavor. Someone who writes an original song or novel is rearranging elements and themes that have existed in other works for ages.
3) "Made up" doesn't mean "something that is 100% original and has never existed before." A BJJ practitioner might invent a new finish for an omoplata entirely on his own, only to later discover a picture of some forgotten judoka or catch wrestler doing the same move 50 years earlier. Likewise, a mystery novelist might invent a plot twist for her latest book, only to later find out the same idea had been used in some obscure book a century prior.
4) Terminology is made up all the time. Sometimes it is made up for a technique that is new (or new to the namer). Sometimes it is made up by someone developing a new art who wants to distinguish his art from its predecessors or to be more descriptive. Sometimes it is made up as an art moves into a culture with a different language. Sometimes it is made up because a practitioner wants more fine-grained description of the different elements in his/her art.
5) In order to be useful, terminology has to be understood. Techniques get named and renamed all the time, but if I were to just make up my own words for all the moves I practice and start using those terms in discussions on this board, then no one would know what I was talking about. In order for communication to occur, people have to know what the terms mean, no matter who invented them.
6) There are a number of factors which can determine how understanding of new terminology will spread.
If you are an instructor and use certain terminology, then at least students at your school will understand the terms.
If you are the founder of a new style, then students of your style will understand your terms. If your style becomes popular and widespread, then even practitioners of other styles may become familiar with them.
If your terminology is useful, because it describes something which is commonly used but which didn't have a widely known name before, then it may spread.
If your terminology is particularly evocative or easily understood, then it may become popular.
If you have some popular communication channel or spokesperson to spread your terminology to the masses, then it may become widely understood.
With that in mind, let's look at some of the MMA based terminology that has been mentioned.
Superman punch: used to describe a specific maneuver where you fake a kick and then use the momentum from the leg motion to power a leaping punch. (It's not just an arbitrary feint, the leg action is an intrinsic part of the motion.) Doubtless the move had been used before the advent of MMA, but it wasn't widely known and didn't have a specific name that was widely known. When it became popular in MMA and someone coined the term "superman punch" it stuck for a variety of reasons.
It was useful, describing a technique that was now being practiced and didn't have a pre-existing name (that anybody knew about)
It was evocative: how can anyone not want to learn the "Superman punch"?
It could spread widely, via the commenters for a televised popular sport.
Abracadabra kick: used by Jon Jones to describe a certain type of faked roundhouse transitioning into a front kick. I learned a variation of the same move in Muay Thai, although it wasn't given a specific name. Jon Jones is a well known fighter, so if the maneuver becomes popular, then his term might stick. Right now, probably no one would understand the term unless they had watched that specific video.
The Showtime kick: used by the MMA press to describe a specific event in which Anthony Pettis managed to pull off what looked like a movie stunt in actual competition. As far as I know, no one is using it to describe a regularly practiced technique. If we get a new generation of Parkour-based fighters who regularly throw kicks while running up the walls of the cage, then maybe that will change.
Vertical roundhouse: used by drop bear to describe a low inside roundhouse that creeps up into the opponent's groin. I'm not aware of anyone else using the term, unless the other guys at drop bear's gym call it that. I think the term is unlikely to spread for a number of reasons - it describes a common technique that already has a common name (low inside roundhouse), it's confusing rather than evocative, and there's no one I know of advocating for its use except drop bear (who is not a well known instructor, fighter, or tv personality).
what's with this 'on the fly' bit mean. To do things on the fly means to be on the wrong side of the law, where does that fit in?
