I can now verify this is true. On my ride in this morning, I bought it on the bridge over the railroad tracks at Columbia and Southwest. Everything was fine until I decided to pedal, then whee! Back wheel goes out and I go down. Luckily, nothing was hurt at all. I think that my clothes in my rear pannier managed to take the brunt of the fall. The next nasty looking bridge I got to, I just walked across on the sidewalk. For those of you who are in STL, I also found out that the road itself was frozen at the top of Cliffton Heights hill on Southwest. For those of you not in STL, the conditions this morning were freezing mist.
On a related note, does anyone know somewhere where they're stocking Schwalbe Marathon Winter tires?