should the die touch the shell holder when full length resizing
In my early days of handloading I over sized the brass which eventually caused case head separation! As I fired the round gasses vented through the hole near the receiver of my Ruger. When I opened the bolt only the case head came out with the bolt. The body was still in the chamber!
Generally you want to avoid too much play in the press leverage. So, begin your setup by first touching die to shellholder, then turn die down another 1/8 to ¼ further.
That is the factory answer to ensure it will chamber but almost guaranteed to shorten case life and lead to case separation pretty soon.. That works but the norm is to push shoulders back way too much.
For long case life and best accuracy yes come back off the shellholder and come down a 1/4 turn at a time until the case will just chamber without you feeling it. Now if you are measuring the shoulder setback you can fine tune to get the ideal .001 to .002 setback.
If this point is past -.002" past the required headspace to fit your case back into the rifle you are reloading for, you have already overworked the brass. If the die is touching the shell holder ,with the slop removed, when sizing a case how much farther can you push the case into the die?
..depends on the fired case size.. if you're measuring -.002 your gtg anyways.. the statement was made as a general starting point, there's no 'one size fits all'.. I agree that if you're not measuring and just sizing to chamber you're apt to oversize or over-bump the shoulder somewhat and resulting short case life.