I was thinking of that. First off - I don't think they offer more than 2:1 leverage, they got burnt pretty badly in the runup in Nov-13.

Second, the slippage you take is about equal to the bet amount, unless you can start an avalanche (which I don't believe).

Third, the bet is not won by just hitting the opposite goal. You need to defend yours for 90 days.

=> You can perhaps use this to make the final push and manipulate the market as usual, but not make it +EV for you