As part of the Minessota Stretching Crew (with Shelton Benjamin) he defended the OVW Southern Tag Titles on a SmackDown! TV taping, likely a dark match, in which he scored with a picture-perfect SSP, drawing applause from the crowd. I even think it was the same distance as his botched WM one, so I'd attribute his missing on not twisting enough because he was quite capable of making the distance.
So to answer Garvinstomp's question, he did perform it at a WWE show but he wasn't part of the WWE roster just yet.
I may have been at the same show as you. I was at a Raw in Minneapolis in June of 2001 and one of the dark matches was Shelton/Lesnar against some jobbers. Lesnar finished the match with a picture-perfect SSP. Lesnar and Shelton also came out to the ring with Jesse Ventura. This was while Ventura was still the governor of Minnesota.
The next night at a Smackdown taping in Grand Forks ND, Shelton and Brock had another dark match but I don't remember him doing a SSP that night.