If they could place an infinite number of bets, knowing that it will converge to 1.97x, it seems like that would make it +EV.
It would seem that way, but it's actually just convincing illusion. The median
will converge back to 1.97, but it won't really help you be +EV. As an example, imagine you flip a coin 100 times, and 90% of them land on heads. If you keep flipping the coin, eventually the amount of heads
will be 50%. But that doesn't mean that tails is any more likely to come up =)
Exactly, a very convincing illusion. The human mind is very alert to patterns and is incredibly susceptible to the "well it's due" fallacy :-P