Track warrants allow trains to move in one direction or both directions and also lets MOW workers gwt into the trains authority. When a train has track warrant it has a the main line unless there is another train out there. When making a meet where i work we use a "work between" with a restriction because there is more than one train. Track warrants are simpler and less confusing than train orders. When you are done with your main line authority you release those limits to the dispatcher so someone else can use those limits. They are simple and easy to use but can be hard to understand at first once you use track warrants they are easy to use just know where you are at so you dont overrun your limits.