The deer I am referring to are in a farming country with all the clover corn soybeans they can ingest available for most of the year, that being said we can tell a huge difference in antler growth in a bountiful wet yr versus a dry one, two yrs ago was a wet yr and there were tons of amazing size deer racks harvested versus 2018 was extremely dry, nice deer with giant racks were a lot more scarce.
I do believe genetics play a pretty significant roll in the outcome, not unlike all domestic animals are bred for the characteristics that one is looking for.

All the really good ideas I've ever had came to me while I was milking a cow.