I'd have to disagree, as much as I appreciate your point of view and previous posts on the matter. Shooting a group that size, equipment not withstanding, is a pretty amazing skill achievement. Sometimes even going over the top with equipment is not a guarantee you will do well. On days when wind and mirage are always changing, it's a tough challenge to still call it and shoot it. Granted, prone or even rested on a sandbag prone makes it harder physically. Offhand even more so.
But, one of the biggest contributions to shooting from the benchrest crowd, aside from how to super-accurize a rifle, is seeing how to call 'conditions'. A lot of newer shooters find it difficult to attempt to master marksmanship position skills along with wind and mirage reading. Too many beginning shooters look at all the factors and rather than seeing them together and adjusting (down to where it becomes second nature with advanced shooters), they simply get overwhelmed. Bench rest takes the physical out of the equation and allows the shooter to decide, under no physical stress, how to call the shot. What is a 10 or an X at short range is a hit or a miss at long range. Translated to the battlefield and precision shooters there, those little factors that can be trained into the mind before the harder part of physically mastering the rifle is a good lead in I think.
All this being said, I don't think pretty much anyone gets there by themselves. Knowledge in this endeavor is passed from shooter to shooter. And so we learn....