I doubt that many of us question the group. And most of us at least would totally agree with the rest of your statement.A well built custom rifle is capable of this accuracy. If they are built right, every one is capable of this accuracy. You often read here that customs dont shoot any better than a semi custom or factory rifle. Yes they do, this is why you buy a good custom rifle. Tuning one to shoot like that is up to the owner however. I do not doubt these groups for a second.
The questions i have and no doubt others also, are about the message in the original post.
And to clarify, would it have been the same message a year ago?