"It is believed sizing the neck makes the neck thicker and or thinner, that does not happen"
Then Fguffey said there is a way to determine fact or fiction and or truth or nonsense, then he implied most reloaders were too lazy or not curious enough to determine what does happen.
I have suggested most Internet reloaders have not been trained to keep up with more than one thought at a time, as in case stretch, Hatcher, a most quoted expert, moved the chamber shoulder forward .080 thousandths knowing the case head would separate when the trigger is pulled, 'it' did not happen, Hatcher became a fire former, the difference between Internet reloaders and Hatcher, he did not spend the rest of his life claiming excessive chamber length WILL result in case head separation, Case head separation as in insipient case head separation is caused by bad habits.
Hatcher did not have a clue, he fire formed modified 30/06 Hatcher .080" cases and did not get credit for his accomplishment. Hatcher could have formed 30/06 Hatcher modified +.080" cases and fired his modified cases in his modified chamber, his modified cases would have off set the length of his modified chamber,meaning he would have fired cases in his long chamber that were shorter from .001" to .005" than the chamber from the bolt face to the shoulder of the chamber.
Back to the lazy and those with no curiosity. Hatchers cases did not stretch in a manner described by Internet reloaders, Hatcher's shoulders on his cases die not move forward, Hatchers shoulder did not move, the shoulder on Hatchers fired case did not move, the shoulder on his fire formed cases was erased when fired, during firing a new shoulder was formed, one more time the case did not stretch between the case head and case body.
Then there is that part where no one measures before and again after, had Hatcher measured the length of his unfired cases and compared the length with his fired cases he would have found his cases shortened, back to being able to keep with more than one thought at a time" Hatchers cases got longer from the head of the case and shoulder/datum, the rest of the case from the shoulder/datum forward got shorter.
I do not live in the little bitsy world of reloading, I form cases before firing, some of the cases shorten in length .035", some of those shorten an additional .010" when fired.
Not possible for a reloader to comprehend the effect sizing has on a fired case if they do not understand the effect firing has on it.
F. Guffey