You find out a couple years later. Like, we KNOW at this point that the Dodgers were at the front of the field in two recent pitching developments that were so obvious and important that other teams immediately started copying them:
1. the high fastball, increased usage for whiffs
2. the "sweeper" slider, new in the last couple years
first you see players succeeding and data trickles in and then eventually you see articles from people like Eno who know what questions to ask
we have yet to see Toronto get accolades for any specific developmental things.