2.
Ever.
The only two times that Slipknot was played when it did not involve Help on the Way and/or Franklin’s Tower were the first two times it was played.
Both of those were Summer Tour, 1974
6/20/74 in Atlanta: Eyes of the World->Slipknot->China Doll
7/25/74 in Chicago: Dark Star->Slipknot->Stella Blue
There were three shows in ‘75 and ‘76 that had Help/Slip/Franklin’s sandwiches of sorts (drums, other tunes mixed in).
The only other variation to its normal placement was in Boston on 9/20/91, when the second set opened Help->Slip->Fire on the Mountain.
Thanks for the prompt, John. That was fun.