So just a couple questions about the interaction between this feat and two others...
question 1. can you use canny tumble while you are spring attacking to get bonuses to hit? this question has been asked before on the rules forums, but it was back in 2012... while it seemed like most people were saying that this was not legal, due to the way spring attack already negates AoOs, there were a couple voices for the other side. also it was two years ago and i don't know if there has been any changes to rules or errata or something...
question 2. when you are attempting a circling mongoose, you still provoke AoOs so canny tumble would work here... at least for the first attack. Would you be able to continuously tumble to get bonuses even though that opponent would no longer be able to attack you?
I would say that the intent of Spring Attack's text is to make its user not provoke AoO's from normal movement.
For instance, if you used Spring Attack with a trip maneuver (I believe that's legal - let's assume it is), and were untrained with the maneuver, it would still provoke. Similarly, the AoO generated by entering a creature's square would still happen despite the AoOs from passing through the threatened being prevented by the feat.
This isn't really spelled out clearly by the feat, so I admit this is my own interpretation. Expect table variation, etc.