Jack, thanks for the additional details about your late father. It had to be a real heartbreak to have the left barrel open up on the VH 12 he left you (and a ton of great memories to boot). Sometimes I think, as we get along in years, those memories are what we treasure, even more so today with both the "anti-hunting/guns" folks, and the city raised who are more or less "neutral" about hunting.
IMO, there is no way to explain this, anymore than your Dad telling you how, for his vision and reflexes, his method of dropping birds with the VH may not have worked in the same manner for you. I could not tell you or anyone what I see (other than the bird in flight) as to barrel, front bead, lead, when I shoot any of my smoothbores- if my life depended upon it. I just shoot, perhaps a bit of what the late, great Nash Buckingham wrote: "The last time I saw a bird in flight like this one, I shot about 'yonder'"--
Both my late grandfather and father were fine wingshots, especially my grandfather- he loved the live bird shoots- and both of them got me hooked on barn pigeons for practice instead of clays. Probably why today I consider myself a better shot on real birds than on clays, and would not spend $2500 plus for a SC competition 12 bore, but would gladly spend that for a well balanced quality side-by-side bird gun(if it fit me and my style of gun mounting)--
We all have our good days, on occasion a few very good days when all seems to break our way, and then we have other days when the Gremlins take over and we don't do quite as well as we wanted to, whether in the duck blind or in a dove field. It doesn't sound to me like your Dad would have ever traded away the 12 VH- he was wise enough to know he most likely wouldn't shoot any other shotgun any better than that Parker you now have. More than even the Parker, he left you some priceless memories and we all thank you for sharing them with us in the PGCA. I hope you will write more about your boyhood with him in future issues of PP.
