Hello again!
I am going to share another “discovery” that I made not too long ago.
First I would like to mention that like the last time, I am not saying that any card is fake, I am just exposing some facts and I am opening a discussion to share our points of view (I also have a beta playtest card (in “good quality” obviously 
) so I have no interest in denigrating them).
Please view the pictures on a computer, not a tiny phone screen ^^
So if several copies of a card are printed in similar quality, it is expected that the copies will not be strictly identical, particularly for the thin lines or thin writing.
Because all papers are slightly different in terms of the fibers that compose them, and so the ink will not impregnate the paper in the same way. Obviously I’m talking about “at home” printing (not HQ printing like for regular TCG cards for example), as this is the case with the proto cards.
For example if we take 2 copies of this Charmander:
There are many small differences in the lines, writing, etc., this is light but it’s expected and it’s visible:
The problem is that there are lot of cards that don’t have these printing differences, the little printing artifacts are the same.
For example if we take a 3rd copy of this Charmander:
We can see that the printing artifacts are far too similar between this copy and the CGC 8:
You can compare all the thin lines/characters of the cards, it’s the same problem everywhere (if there are tiny differences, it’s not the impression, it’s because the 2 scans are not strictly identical and not perfectly straight).
It is possible to do this comparison for a lot of other cards and find that 2 copies will be very very similar, while the others will not be (as expected due to the “at home” printing process).
So what do you think?
I don’t want to believe that there are fake cards, but I don’t particularly see any logical explanation for those facts here…
EDIT : I took a Delta card for my example, but this is the same for Beta cards too ^^
EDIT bis : Just in case, I made the test “for science” at home, if I print (in regular quality) the same thin text or lines or whatever, 3 or several times, I will always have a slightly different result (like for the Charmander AU and CGC 8), as expected.