My friend's bookie normally has lines at -105. However, when lots of action goes to one side, he'll change the odds to Even and -110. If even more action goes to the same side, it'll change to +105 and -115. The spread does not change, only the juice.
My question is, assuming the spread is correct and it is a 50/50 on which side covers, is it not +EV to always bet the +105 side? I'm a poker player and know very little about sports betting, but I know that if I'm getting 1.05 to 1 on a flip, I'll take that any day. So I was planning on just waiting till his book is unbalanced and always betting the +105 side. No research, no nothing. I trust vegas that the spread is a 50/50.
Am I correct in thinking this? Does this have a positive expectation for me?