I mean, cannabis roots dont really grow like that. Maybe the main tap root on a plant from seed but not from a clone.
If you look at the image below you can see how the roots grow. Most of them grow out not down. Water roots grow down. feeder roots grow out. This is why top dressing works so well. I stopped doing all the transplanting after I saw this. This is why I want them in their final home as fast as possible. Get those feeder roots out and into the mulch layer as fast as possible. If I was trying to control the rate of growth of the plant then I could see this.
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Now for a tool to keep noobs from overwatering thier plant, then yes. I wouldn't tell someone whos new to growing to not do this. But for someone who has been growing for a long time, this extra labor isnt worth the time imo.