https://news.ycombinator.com/item?id=36766556#36768937
Like with trading systems, the thing that made it work here was not being smart about the maths. In fact anyone with high school maths would be able to work out when it was worth doing.
The thing here was the audacity to try to put together a business around getting it done. Things like getting investors, figuring out how to print the tickets, and delivering them.