Zombiechopper,
Mainly used for bolting/unbolting the fishplates plates on the track. Most CN rail was built with continous track, but every switch line etc, has all kinds of fishplates on them. Big Joe with a 10' breaker bar wouldn't break some of those nuts.
All our local lines got pulled up this past summer, was neat watching the miles upon miles of track already pulled head down the line. My son is only two years old, but he got the chance to see the last locomotive go past. Been near four months since I have heard a whistle blow..............except for the Thomas the Train one.