the young dumb ones are the first to go on a wild chase when the does are not ready yet. I do believe the older bucks wait and many will be bedded by first light even during the rut and ONLY move at mid day when the does are bedded (and many hunters not in the field) and approach from downwind of bedding.

I have also seen some old bucks bed in the smallest spots a hunter would never think to look and ONLY come out at last light to check does.

I agree with your point, the Mature bucks are often the last ones who enter a field.

The 1.5 and 2.5's yo's are the first ones which end up in the backs of trucks on opening day though!