I don't know who you were watching but we sure didn't go slow.
The straight stretch went up the middle of the river for about 2 km or so I'm guessing. More than enough time to build up as much speed as you wanted. Then quickly realized you 'didn't want it' on the turn at the end.
We had enough room that even the snakey parts were big. Also, the river was almost never a shiny, slippery surface. Rarely could you skate on it for instance. It was more likely covered in a light layer of snow after the track was roughly snowblown by a small team of farmers with big blowers on thier tractors. The snow kept the ice soft underneath and was probably a lot more grippy than you might be picturing but yet still pretty crazy at speed.
I don't know what you saw, but I'm guessing our version wasn't anything like it. Hmm....I wonder if I could convince anyone to start it up again.......
