I think it is the other way around. You examine the ink first, then the stock. After all, one can print or forge an autograph on old stock.
However, it's not an either/or, and, of course, you examine both.
If I had the item in person I would be looking at the printing through a microscope. Paul provided me with large closeups, that allowed me to examine the printing. When people send me digital microscopic images-- and there are digital microscopes that allow you to take images--, I can examine the images as if the item were in person.
Identifying Antique Commercial Printing Processes, And the Basics of Authenticating Antique and Art Prints