Peri whisks the Aztlan/Aztechnology delegation out of Denver to Las Cruces before Ghostwalker was about to assassinate them all. It's not something Peri should be able to do. It's not something anyone should know how to do, except maybe some Great Dragons or immortals. It's not teleportation. The closest explanation in the shadowtalk is that it was some sort of supercharged Levitate spell. Peri's stats mention he knows a custom Levitate spell, which I wouldn't even have mentioned. The whole point is that no one knows how, why, or what he did.
But I love how we cannot put one relatively minor thing in the books that defies explanation, or simply shouldn't get one, without someone calling into question the entire setting and the competence of me and the other writers because ¯\_(ツ)_/¯.
If it shouldn't get an explanation, then the book shouldn't feature half a page discussing what that explanation could be. The topic of those discussions could have been an excuse to introduce another plot or have an exchange between Jackpointers that emphasizes their character traits or whatever, but it is not. So half a page of wasted paper would call into question the competence of writers. But most reader actually trust the author enough to infer the existence of an explanation from the very fact that the author wrote about the search for one.
Despite the exhortations to "defy the audience's expectation," there are still things that are proven not to work. If you introduce a mystery, then you either explain it (even if it only at the end), or you handwave it. But that's a one-way door. If you started explaining it with theory, you'll frustrate your audience if you ultimately handwave it. And if you openly handwaved it at first before suddenly making the explanation important, you'll just look stupid. Of course, that's the kind of rules that you can ignore if you're a skilled writer (but chances are, if you're skilled enough to do that, you already know about it).
Shadowrun is a tricky setting to have mystery because it has science, technology along with magic and actual written rules for magic (or at least some of the magic). So there can be a really fine line between explaining and handwaving. To a number of people, "dragon magic you cannot understand, you punny mortal who follow the rulebook" falls on the handwaving side. But that line moves based on one's knowledge. Your most typical case is a sci-fi author thinking he is handwaving something using tech jargon, while a part of the audience with appropriate technical background will instead take it as an explanation that is WRONG. But it can also goes the other way, with an author or GM going all fussy about, say, "He's an adult dragon, not a great one, he should not know how to do that!" while most of his audience are totally oblivious to the difference between adult and great dragons beside size.
In the end, it is mostly up to the fact that you're part of a team, even more so as credits don't list who authored which part, who has a record of timeline, geographical and consistency blunders that got noticed. There are people who consider their numbers to be within acceptable limits, and others who don't. And among those, you now have people ready to jump on what they think is the latest blunder. And once they start thinking you are stupid, they systematically apply "Hanlon's Razor" without giving it a thought: never attribute to malice that which is adequately explained by stupidity.
For some reason, this reminds me of someone who was mocking the
London Sourcebook because SAS action as a secret police force did not match what he knew about this unit, seemingly oblivious to the fact that British writers who lived through the 1980s may have known better.