[repulse]

Construct simplified poker situations with general and specific large differences in play skill between players at the table and derive the expectations of each player. Observe that the more rational/strategic players have positive expectation at the expense of the clearly irrational players.

Then supply statistically significant real-world evidence as to the existence of players with positive expected value in poker games.

Anyone who would not be convinced at this point would either be confusing the question at hand or presupposing that basic probability theory is voodoo.