No, I didn't.
Unless you repeat these very same things hundreds if not thousands of times over then it will just continue to appear random to us.
No one is quite sure how the developers have programmed the game, but we do know they have done it to make consumers spend, by slowing training speed as a player ages. You have shown an anomaly in one instance but it needs to be repeated over and over again for us to have an understanding
A couple of guys have recorded things like this and put them in spread sheet form, and it's great, but even that gives a very limited view of how things work overall