Well Mr. Fox, your questions are well covered by the gentlemen who responded above.......I will simply add anecdotical information as to how my hunting style has evolved......I don't actively hunt "singles" following a covey rise. There are however situations where previously flushed single birds will be pointed by the dogs while in pursuit of the next covey. My call on shooting that flush is dependent on the dog(s) involved. More directly whether it offers a training opportunity for an unfinished prospect. I find such occasions opportune for ingraining the Dog-Bird-Gun triad in the mind of an impressionable dog. The connection of the point, the flush , the shot and hopefully the downed bird for the dog to mouth/carry and receive praise for the success he/she has contributed to helps make a country dog come around quicker.
In that same vein I frequently look at a covey rise with intent of picking a target bird that is in the easy peripheral view of the dog I want to school on. Hopefully to carry out the same procedure as outlined above.
An interesting take on the process of concentrating on shooting cocks over hens was first shown to me by its originator, Dr. Dale Rollins. His game of "Quail Snooker" is to encourage shooting roosters over hens. Usually causing one to "lose' the match after taking the third hen of a shooters outing. It will make you look a little closer.
Since I generally gun alone (by preference) I am given a good deal more flexibility in my gunning choices. Not the least of which is a higher shooting percentage since the gunner does not have to make a "safety check" of his companion gunner's location before picking a target. If I have a good view of the dogs on the ground, knowing my horse ( or vehicle ) is behind me, and the shooting field is anything 5-6 feet or higher off the ground. Makes for a higher kill percentage.
Conditions look favorable for this afternoon, and i intend to put in a couple of late afternoon hours behind a rested dog pack. Hopefully the birds will cooperate and some will fall into the scent cone of my loyal canine pals.
Yours in good Sport