I learned a lot from one of the guys that broke off the trick it thread and set up a private slack a few years ago. He wrote up these long PDFs about the inner workings of the ticketing systems, I think he was a former tech guy at one of the distribution systems so he knew where all the vulnerabilities were and how to hunt and peck with some method that would uncover them. I tell people now that the lowest cost deals are usually OJs or double OJs and often involve plating by multiple carriers or with multiple fares, because of how the airlines have all outsourced YR/YQ calculations to a separate service provider (and it is gltichy as heck). Plating someone else's fare is a risky proposition, you better know exactly how they set base fares and whether they use YQ/YR to essentially guarantee a floor cost for a certain route. A new entrant like EI is learning that the hard way as they sign on to more codesharing agreements. The days of decimal point errors are (mostly) gone, the sweet spot these days is these things. I picked up LAX-HEL-MXP//DUB-LHR-LAX last month for $1,700 because I was just randomly trying origins and destinations in a template I use on ITA Matrix but focusing on DUB. When the receipt arrived for those tickets, it was pretty clear why the deal was so good, EI only charged $150 in YR/YQ when it plated AY fares. We saw (and still see) similar fares (like FCO-US-FCO) on EI when booked through AS.com. Those $750 per direction fares are still there and they suggest to me that perhaps EI is a good carrier to mess around with in other places and for other routes. They have stopped plating AY fares for the time being ;-) But it seems too coincidental that EI and DUB are involved in many of the lower priced tickets I see the last few months... hammer away folks, there are probably many more hidden in plain sight.