Shall we play: what if?
If pressing were to be suddenly detectable 98% of the time and agreed to be considered restoration by CGC, would CGC be willing to initiate the marketplace upheaval that would be bound to ensue?
I believe detectable pressing would work to dissuade future pressing, but a lot of books would find their way out of a blue label and into a purple one over the next few years. Especially should it prove necessary to reslab books after seven years or so. The purple label could kill a lot of aggregate market value very quickly.
But if pressing is restoration (and I think it is), could it not be viewed as suggested in an earlier post by Burntboy as a less egregious form of restoration?
Could a pressed book fit comfortably in a blue or green labeled slab with the notation "pressed"? Would this lessen the integrity of a blue label?
p.s.
I am really playing the devil's advocate with myself, here, as I am not a fan of any type of restoration, short of the conservation necessary to keep a very old and very damaged book 'alive'. I am still worried that pressing might structurally weaken a comic book over the long term. (With the relatively recent historical introduction of pulp paper and its fragility, I worry that damage might be done on a molecular level and only become apparent as years pass.)