I don't think so. With these horror books, it's all about having the highest-graded copy to guys paying the insane prices. It may only be a small number of guys competing for the highest-graded copies. If that's the case, it might only take one or two guys dying for prices to collapse.
I care more about having white pages than having the highest grade, and fortunately for me these number-in-the-corner guys don't seem to care about page quality, so mid-grade copies with white pages are often still affordable.