To Cull Or Not To Cull; That Is The Question

You have to be able to "read" pigeons. Kit watching, from liberation through flying and down and it is mandatory. So are the many hours of in coop watching. You can learn more from just being alone with your birds than you can by bullshitting with other roller fanciers.
In order to establish a quality gene pool that will consistently produce uniformly sound rollers (presumably acceptable to mother nature) we will have to attenuate the heck out of our present stock-with nature's system in mind. Everyone has a few good birds and that's all that's necessary to begin the process. We start by eliminating the culls. The obvious culls are:

(1) The sick and puny birds. (nature always eliminates those first) Humans tend to treat the sick and nurse the puny. Bad idea and short-sighted!

(2) All roll downs must go, even youngsters after their first thump--no matter how accidental it appeared to be

Many are in conflict with this point.  Read page The Value of Rolldowns