Card doctoring...

[Throttlesteer]

You're handcuffed in a way. The internet has brought accessibility to cards you probably wouldn't be able to find otherwise. The ability to identify alterations, prior to purchase, is impossible without having the card in hand. It doesn't matter if it's encapsulated or raw; Your chances of getting duped certainly go up if you buy raw from an unknown source. But, some of the more respected names still make mistakes. They turn an awful lot of cards in a short period time and, like many, also trust the grade without further examination. Does it make sense for sellers to break out the eye loupe for every graded card they sell? I don't like the doctoring any more than anyone else. But, it's hard to make a case against someone without firsthand proof, as Leon pointed out. It would be irresponsible to "out" someone and ruin a good reputation, simply because a single card graded by a respected grader ended up being altered. Just my two centavos.