The Safety Committee falls under the National Master under Article 18 Section 20. I guess the number of people that even bother to read the contract equals about the same that bother to vote for it.
My Center does have a driver lead committee that includes our shop stewards and Circle of Honor drivers. They are active and I used to be on it. It is a way to get off the road every once in a while and I used to do it. My Center is allowed about 80 hours a month for Safety work. I once made up the Six Month Plans and did data entry into the Liberty Mutual site. I used to mentor new drivers and I even rode on the car all day with a few of them. That was the most useful part where I thought that I made any kind of difference. I did get tired of it and I resigned when they started over-dispatching us.
Back to the original topic. We do have certain trailer loads that may get rolled a day to even out dispatches to my understanding. They are probably Basic or heavily discounted shippers with relaxed guarantees.