A lot of the knowledge is very arcane, and like, split over hundreds and thousands of flyertalk.com pages, and like... institutional knowledge of more clever travel agents.
I think a lot of the "fun" that can potentially be had also requires a direct access to a GDS, which, AFAICT is on the order of ~$10k a year?
And if your "tricks" are discovered, airlines have a direct way to demand payment for any shenanigans you've pulled (ADM, https://www.ana.co.jp/businesspartners/en/admacm-policy/). But perhaps OP had something different in mind, I'm curious myself now :P
If you wanna really go off the deep end, try looking into "fuel dumping" community — there's a small group of people who basically have figured out a series of bugs in how fares are coded (that lets them buy flights much cheaper then intended).
They use (very dumb) coded language to talk about their "findings", and are very very very unfriendly to newcomers; but it's a fascinating world to observe.
I have been able to save USD 500 with a VPN (booked Aeroflot ticket advertised on Russian google with a Russian IP). I am able to read a little bit Cyrillic so I was able to go through the booking. Citibank then blocked my CC and called me. Did everything again and got the ticket for USD 1000 instead of USD 1500.
Good experience with switching languages on sites. I was able to buy tickets 80% discounted by switching from English to the native language.
Fuel dumping is probably a much smaller deal then it was a few years back!
"blogs" ruined a lot of tricks and fun for some; but my understanding from observing the FT thread is that there are still people involved, just on a much smaller scale.
Enjoy while it last. Some Idiot always has to make a blog post to collect some ad revenue or some attention. People don't understand that you can only use a loophole, if few people know about it.
Bullet train tickets in Germany are expensive. You were able to buy them online in the Czech Republic for a fraction of the price. Like Prague->Brussels 20 Euro. You don't have to use the whole ticket, you boarded in Frankfurt and went to Brussels for 20 Euro.
Revenue manager of any, every airline will catch up to you but some of them are nice. Many are not. :)
Direct access to an GDS can also come way of an OTA, which, may not sanitize input properly, or if you learn how bulk purchasing of tickets happen (e.g. if airline is sold out, but it still shows/bookable by an OTA they have access to bulk ticket fares and can sell - sometimes flights close out on the airline but are bookable to last minute on OTA as well.)
Flyertalk is a great resource, and also, surprisngly the reason why Whatsapp was created too! - But I wasn't being indicitive of that and knowing what a fare code/y/j/whatever class fare is - I meant that sabre/amadeus and the front end of the airline are really "broken", and you can do similar things to what the original article posted, even abusive things like "walk" for tickets to refund to an airline hosted "Wallet" (usually you can attach a PNR and reuse it and rebook a new PNR/Ticket) which can break the chain and require someone at revenue management to really pull the log for that coupon/PNR to see where the money went, or why someone else flew that segment.
You can also double refund - and of course the airline can clawback - if they find out in time. Though many airlines have special gateway relationships w/ banks (as noted by the point system tied to a credit card network) (But this comes down as general fraud.)
The fuel dumping community isn't the only one, the reason they are unfriendly to newcomers is because they think they got a neat trick and they do, and once it hits front page news, that fare/date is dead. But there are other communities similar too - there is the staff travel/non revenue community which flies for free*, buddy passes, companion passes or on Zed90 tickets which is standby travel on OAL, other airlines (though you need to be listed/included on someones benefits.) and travel industry IATA or something - and thats the thing, if you can get access to a GDS and encode fares you may be able to list yourself but these aren't normally commercial fares, but I've seen many times a GDS spit out wrong class, class mismatch, fare/class mismatch, etc that wouldn't be a mistake fare per se, but a misconfiguration or a unsantized input that did this :)
But also, some GDS's are also nto that locked up, you can find some on shodan if you know the right keywords and literally poll someones name to see if they have any active flights, etc. I'm not encouring anyone to go find them, but if you know what to look for, there are many insecure or generally not behind any login page that opens up to a general query and allows reservations and confirmed commercial fares - but that falls down to just poor IT security operations in general vs GDS flaw.
tl;dr All Airlines front end/ecomm site talks to it's own GDS which are cloud hosted but act like 90's shell programs, some/many ecomm front ends are really bad and you can do stuff you shouldn't. It all comes down to your identity and is all tracable which is why many of these flaws still exist, because it's enforcable the other way/tech debt to fix is too much.
And we haven't even got into SSR codes, OSI codes, etc
Then imagine: buyFlights.php?sabre="1DFWSFO12JAN23FEB+etc..."
If you've ever seen your passenger name come back as ALL UPPERCASE, it's likely been washed through the methuselah of systems, and those systems have lots of internal quirks and commands that may let you do things like switch seats, add a car, drop a passenger, change your meal preference, etc.
"some/many ecomm front ends are really bad and you can do stuff you shouldn't"
...if you pay attention to what's going on "in the system", if there's an unprotected endpoint where you can say "LUNCH=vegetarian&&btw-duplicate-this-flight-then-cancel-and-issue-a-refund-in-cash", that's (sometimes) the level of badness in the different systems.
Historically: SABRE was a spinoff of AA and one of the first real database / computer / IT companies. EaasySabre (ca: 1986!?!!) was one of the first "credit card over modem" applications (eg: on Prodigy!) - https://www.travelweekly.com/Travel-News/Travel-Technology/S...
...lots of opportunity for "legacy" bugs hiding there.
I think a lot of the "fun" that can potentially be had also requires a direct access to a GDS, which, AFAICT is on the order of ~$10k a year?
And if your "tricks" are discovered, airlines have a direct way to demand payment for any shenanigans you've pulled (ADM, https://www.ana.co.jp/businesspartners/en/admacm-policy/). But perhaps OP had something different in mind, I'm curious myself now :P
If you wanna really go off the deep end, try looking into "fuel dumping" community — there's a small group of people who basically have figured out a series of bugs in how fares are coded (that lets them buy flights much cheaper then intended).
They use (very dumb) coded language to talk about their "findings", and are very very very unfriendly to newcomers; but it's a fascinating world to observe.