The AG program is designed to VERIFY YOUR IDENTITY, not to determine that your callsign is a licensed callsign.
Since anybody can print off a copy of YOUR license at the FCC web site, and since you would not want someone to use YOUR license as proof of THEIR identity, we cannot accept these for AG.
For example, go here:
http://wireless2.fcc.gov/UlsApp/UlsSearch/printAuth_amateur.jsp?licKey=780866Print that license, sign it, and submit it to us, and it will prove that YOU are W1AW. Is that what you were expecting? Probably not. ARRL would sue us, and we're not interested in paying membership donations to a lawyer.
So, you must submit the one piece of paper that ONLY YOU COULD HAVE, which is the original license, printed on safety paper, that the FCC mailed to you, that you signed, and which proves your identity.
Of course, that's just my opinion... I could be wrong!
73,
Dave Morris, N5UP