Reliance on numbers is the best predictor of future success and in fact does tell the future story within a standard deviation of two percent. If we look at prospect ranking, wherein historically Baseball Prospectus has been the best predictor of future WAR (versus Baseball America or Sickels) at the major league level. But when evaluating prospects future mlb value, it does not stop there; within a given evalution of a player draft ranking historically has been a very good predictor as well as factoring in organization/team where said player is developed (the best teams statistically have been the Indians, Rockies, Phillies and Mariners). College players with at least one year attendance have almost a 6% better chance of being a successful mlb player versus those who don't attend (all other things being equal).
If Teoscar is 2 WAR player the Jays will not be surprised cause they aren't expecting anything more. If they get something better, it will be gravy.
What does all this mean? Two things: 1. A lot of thinking goes into ranking propects and the numbers certainly play a big part. 2. No one on this board should take tercet's bet, chances are you would lose.