Connecting SNES Controller to the Steckschwein

Recently, Michael Steil published a blog post about connecting NES and SNES Controller to a 6502-based system showing how to use NES and SNES controllers on a C64 without the need for any special hardware, by just connecting them to the C64’s user port. Why not use his approach and adapt it to the Steckschwein? The Steckschwein has a User Port, too, albeit a very different one as the C64. Basically, the Steckschwein-User-Port consists of the complete Port A of the VIA, plus the /RESET and /IRQ lines.