It's probably NOT smooth. Looks like he's already been down that side once. I have to do the same thing with my driveway to get dirt/clay back where I want it. I usually have to wait for a light rain to soften it up. Or doze the wash-outs within a couple of days after a hard rain.
He's using the scarifier, which is buried to the beam, to rip up the roadbed so the blade can then be used to distribute the material. Most old machines carried a scarifier because the machine didn't have the ability to tear up a solid roadbed.
The operator has a steering wheel to make small direction changes or corrections while grading. If the task is to turn around, the steering wheel will be used along with track clutches that disengage one track so the dozer is also wanting to turn the same direction. Even then it will require a lot of space and many forward/backword moves to turn around.
The two large control wheels by the operator raise and lower each end of the cutting blade. The small control wheel to his right side is used to raise/lower the scarifier.
There is a lever in front of the operator that is used to release a latch pin which holds the cutting blade in an angled position. Once this pin is released ground pressure is used to change the angle of the blade. Then reset the latch pin to hold it there.
The blade table can be repositioned under the machine to do ditch work by mechanically removing fasteners and then using the machine to push the table to the position required.
The blade can also be unfastened from the table and shifted to either side for similar tasks as ditching or reaching far outside the track of the machine.
Pretty crude but considered a Cadillac in it's day!!! I started running a grader 32 years ago. A CAT 12 machine with mechanical blade controls. Compared to today's machine it was about as effective as dragging a chicken backwards down the road....
Here's a predecessor to the pictured grader above. This was pulled my a dozer. I bought it out of an iron scrap yard. It's a CAT Model 34. Same controls as mentioned about just different power source. I put my Son on it one day and pulled him around for a couple hours. He decided the men that ran these all day were very tough.