Lloyd that is some great advice.
Yesterday I had a buddy that only shoots his handgun right before handgun season, just to check the sights and see how he does. He shoots at 25 yards only. Well he had a shot at a doe the other day at 44 yards and missed. He went to the range and shot the gun once again at 25 yards. 2 shots hit close to center, and the other 2 shots were not on the paper. He ask me what was wrong with the gun or load.. I told him let me see the gun, I loaded up 6 shots and shot all 6 shots in a 2 inch group off hand at 25 yards. I told him nothing was wrong with the gun or load, it was the guy behind the trigger.
I told him, about the same advice you just gave. I told him to shoot his gun at 50 yards and get real proficient with it. Once he can hit a pie plate at 50 yards with all six shots, then when hunting don't shoot anything over 35 yards. He ask me why only 35 yards. I told him is adrenalin and excitement would not let him shoot as accurate, for several reasons. Then I told him, he needs to shoot is gun a hell of a lot more then once a year.. ..
That is what I find with a large amount of handgun hunters, they think because they can sit at the range and shoot OK and I use OK loosely., that they will go fine in the field. Then I try to tell them the further they shoot, that not more steady they have to be, at a distance the movement of the gun movement is multiplied by 15 to 20 times more at longer distances.
At 25 yards a slight movement of the gun may not show much, but at 75 yards that same movement will throw off the point of impact off by a Hugh margin.