Muley Buck
WKR
Not so with the Co-Ax. If you scrub to 8:26 you'll find your explanation there.somewhere i have seen it in print that you should achieve .002 crush of the anvil into the primer cup. with a press handle feeling the primer go in and bottom out is about all you can get. you cant feel that little extra crush that a hand primer gives. with the hand primer [ even the lee] you can really tell if the pockets are loose.
with a press you can crush the primer too much they claim. i am not sure where that point is or what the result would be.
i am pretty sure most folks are just fine with a press and will rarely , if ever, have trouble. i used a press up until the late 70's when i started to follow the accuracy crowd.
we do have a lot of choices and there are many ways to get good results. if you are getting good results that is all that matters.