After video surfaced of a TDOT driver swerving all over the road, the state agency explained the use of the "slow roll."
It's interstate video that may shock and anger some drivers. It showed a yellow TDOT Help Truck weaving across four lanes of traffic flashing the sign "Do Not Pass."
All drivers behind the truck were forced to slow to a crawl on the interstate. You can hear the aggravation from Israel Amaya who posted video of the incident to Facebook.
"This ------ ------'s weaving all over the road!" he can be heard exclaiming in the video.
He wrote on social media that the TDOT driver was putting people's lives in danger and asked others to share his post.
He gave NewsChannel 5 permission to use the video, though he declined an interview.
Despite that, you can hear his feelings loud and clear when he pulls up to a second TDOT truck parked near a broken down car that was now on the right shoulder.
"Over this, he was doing all that over this!" he said upset.
"It's a very accepted form of traffic control," explained TDOT Spokesperson BJ Doughty.
While the scene of the weaving TDOT driver may be unusual to commuters, she said for TDOT workers it's a regular part of the routine.
"We had a person with a disabled vehicle, they had a flat tire and a dead battery, and they were stranded in the left shoulder," Doughty said about that incident, "which is a very dangerous place to be."
She said the left shoulder is much smaller and it's right next to the dangerous fast lane.
Being behind a so-called "slow roll" may be inconvenient, but Doughty said it's better than the alternative.
"If that car had stayed on the left shoulder you could have been looking at delays while the tow truck came and blocked off the left lane. So at the end of the day it was the much better way to handle things."
TDOT does usually prefer to use multiple trucks to slow roll traffic in order to move cars out of the way.
"In an ideal situation if we had two trucks available we would deploy two trucks so they would just block two lanes each. And so it does look a little bizarre [to have one truck covering four lanes]," she acknowledged.
TDOT officials have seen the video as a teachable moment.
As more people move to Music City, crashes and incidents will likely increase. That means you could encounter a slow roll when you're on the road.
"Our help drivers are out there just trying to help people every day. That's what they do," Doughty said.