The talk on all the pods and shows seem to indicate Rivera doesn't buy into analytics and makes decisions based on gut feel.
I don't think this reputation is entirely accurate. He just hired a VP of analytics.
He also signed an UDFA RB who charts among the higher rated prospects according to the number crunched.
https://www.footballoutsiders.com/st.../backcast-2021
Patterson is the 8th ranked RB according to the Backcast metric.
Definitely worth a flyer on an UDFA.