What percentage do you think may be capable of legitimately providing such proof? 3%? 5%? What would prevent those who are already experienced in passing forged documents from forging such similar "proof"?
I was not really active in politics when the last amnesty went through, so I don't know how much fraud there was. I have no problem learning from any of those past mistakes and making sure those who apply this time can prove they were in the U.S. prior to 9/11. What kind of "proof" would satisfy you?