Test Any System in an Afternoon
You do not have to take this page's word for it, and you should not. Take whichever system interests you, write down its rules precisely enough that another person could follow them, and apply it to a hundred rounds in a practice mode — logging every result as it happens rather than reconstructing afterwards. Then apply a fixed stake with a fixed call to another hundred rounds and compare the totals.
Two things usually happen. The totals land close together, both slightly below break-even, which is the edge appearing in a sample large enough to see. And the system turns out to require judgement calls at the exact moments where it matters — which is how a method survives contact with evidence: by being flexible enough never to be wrong.
Why the Trick Market Is So Large
Because it sells to people at their least sceptical. A player who has just lost a session is the ideal customer for a product promising the missing piece, and the channels where losses get discussed are exactly where these products recruit. The pdfs and charts cost nothing to reproduce, need no infrastructure, and can be sold indefinitely to an audience that renews itself with every bad evening.
For the mechanic underneath all of this, see the big small game guide. For the mod files and predictor apps that sit alongside the chart-based systems, read the hack claims page.