That thread gives the technical details. Here's the goods, from the same dude:

Paul Rozelle's 24-hour, pre-PBP, fixed-gear, Mont Ventoux ride

"Fame and glory (and masochism) aside, I believe that just about anything that can be done on a geared bike can be done on a fixed-gear. Ventoux has been climbed by fixed-gear riders before. It was probably the usual means of ascent for a long time, but that was so long ago that most people have forgotten. I wanted to restore some of that memory and perhaps inspire people to push their own limits in cycling. Doing both Ventoux and PBP in the same week would help make the point in a more extreme fashion: if this can be done on a fixed-gear bicycle, then tell me what, exactly, cannot?"