funny you should ask this ol' buddy..
here are some numbers regarding NBA spreads only, using 16 points .
if you moved the number 16 points either way here are the results.
Middles = 771 times
Fav = 48 times
Dog = 77 times .
meaning the only team that covered the movement was the favorite teased down 48 times and the dog teased up 77 times.
all other games didnt matter . they middled.
so basically taking the dog got you around 95 % win rate. 848 wins , 48 losses.
dont have the info on totals .
i can tell you that college basketball when taking all the dogs up 16 points , you were hitting roughly 93 or 94 % . most of those being middles as well..