Invest in 2 or more sport books with big bonus payments. Looking at the hockey lines for example one sees over 5 goals at some books and under 5.5 goals at others. Bet the over at one and bet the other at others. Other situations would be lakers-5.5 points at one book and spurs+6.5 at another book. If one keeps betting like this looking for middles and arbitrage and big bonuses could we win on a consistant basis?