That rule really is stupid. I don't file many amended returns, but when I do it is usually correcting someone else's screw up. And I was kind in saying that. That just plain sucks.
As a side note, if that comment is spam I think they really need to start marking all of the Turdddotaxxer posts as spam. Your post was valid, Turddotaxxer posts are inappropriate in a professional tax forum.