Considering the amount of money to be made, I think it's reasonable. I present the following:

1) Get the original (say, $3000 coin) carefully out of the holder - then smash the holder with a hammer.

2) Find a replica of that year coin, which really is a fake, for $10-$50. Scratch it up, bend it, whatever.

3) Send the original coin back for grading to be certified with a new graded coin holder and serial number, to be sold for $3000.