Not exactly. The tweezers are used to pull loose soil out from between roots. That picture still shows the root ball with soil.
Brian’s picture was taken after the roots had been washed with water. Completely bare rooted.
If you look at the picture after the full cut back of roots was done, you will see that the feeder roots are about the same color as Brian’s. Brian just keeps a whole lot more of them!
Here’s what will happen:
On my example tree, more structure development is desired. Rather than more ramification. So, to get that, we want more root growth. The roots have a nearly empty pot to grow into. The roots will extend rapidly. And so will the new shoots of twigs. Which will thicken branches.
On Brian’s tree, the roots already pretty much fill the pot. There’s not much soil available, so they will start to circle fairly quickly. Root growth will be contained. This will cause the new shoots to be shorter, have shorter internodes, and smaller leaves. Brian’s method is used when he’s happy with the structure of his tree, and just wants more ramification.