Transit time after RNY???

Have any of you ever heard of Transit Time after RNY??? I'm trying to research this topic. It's suppose to be the correlation between 1) Pouch size 2) Anastomosis Size 3) Length of Roux-Limb and the rate at which you process your food intake. I'm trying to figure out ...is there a normal rate of transit that deems an RNY successful weightloss rate? If anyone has any reading or websites on this topic please let me know.
Thanks,
Kathy