It's a little difficult for me to put into words...I guess the best way to explain it is that if all I had offered to me was under 8.5 -115 I would pass, I dont have it as a strong play at all, it's only a lean, and IMO a couple of shops WANT action on the over. On leans I want to be +EV, this play isnt, but the book's opinion kind of makes it +EV, if you know what I mean? As far as the value of half-runs, I pretty much stay away from that type of stuff. The books probably have some of the strongest numbers over time for half-runs, but that can be a WEAKNESS. OVER TIME the books make money on these statistics- that is why they use them. We make money in the SHORT TERM, by finding value in the single day. The books know they will get enough of people's money over weeks, months, and years with their SLOW MOVING adjustments. I'm not sure if you find this an answer to your question, and it may not make sense, but it's a sort of philosophy that I follow, one thing I tell the not-so-statistically inclined is "the books have to hang the lines, all we have to do is choose the right side" and in this case, given key market opinions and offered an over 8 -115, under 8 -105 I'll take the under. At 8.5 -115 I'd have to like it about 10% more.