I don't think that telling a man that he is using a false assumption, which is leading him to a wrong conclusion is humiliating him at all. Its the straightest way of telling him that his problem lies with his sources of information, and not his gun. I would not humiliate anyone knowingly, and I did not intend such here.
Perhaps you have a block on your shoulder waiting for someone to bump into it.
Using plastic sabots in his barrel to hunt deer is not necessary. Using pistol bullets in his rifle is not necessary. A lead Round Ball is more than adequate to kill any deer, which is what is stated objective was for asking his question. I was hoping to save him from wasting his money on gear he doesn't need. Whoever told him to use that stuff failed to mention his need to have some special solvents to get the plastic out of his barrel, in addition to the costs of buying the bullets and sabots. And they failed to tell him that he would take twice as long cleaning his barrel because he would have to use a solvent to get the plastic out of the barrel, and then soap and water to get the powder residue out of the barrel, whether he shoots Black Powder, or one of the new substitute powders. And, I suspect that no one told him how much more costly the subs are, or that they require a hotter percussion cap to ignite, and should not be used in flintlocks, etc.
If he has been humiliated by anyone, its the guy that steered him wrong with the advice to use pistol bullets and sabots in the first instance.