I have a version somewhere in my library where the card is loaded from the bottom of the deck, in Kelly/Ovette fashion, but with the cardcase on the table. I only have time to check one book; let's see if I can find it.
Well, I thought it was in Best of Spades by Bob Bengel, but now I can't find that in my library, so I can't confirm or deny. I do remember one pointthe case was at the edge of the table so your leg could brace it for the insertion.
A quick check online shows a trick called "Caseload" in Best of Spades. It apparently appeared in the Magic Menu on page 668. That must be what I was thinking of.