100% of those guys complaining on that video have never owned a Busse and were never going to buy one.
There are always aberrations and it's a basic concept in scientific testing that a sample size of one is meaningless.
Over the last couple of months I've done probably ten field trips into the Australian bush and carried a battle mistress every time. I've been clearing vegetation, digging dirt, hitting rocks - without even a tiny chip or roll.
The last trip I did, some exploratory bushwhacking into a remote area:
You can see how thick the vegetation is behind and to the side. It was like that right up to the tree trunk. I cleared the whole area around the tree using the battle mistress. The knife was chopping hardwood, going into the soil, hitting granite rocks, without any damage at all. I've done that three or four times over the last month. (Why was I clearing it? These are post-fire weedy shrubs and juvenile trees, stinging nettle and the like, so there is no problem with clearing them. They will naturally thin out any way. And I wanted a photo.)
After a bit of use the knife is dirty but unharmed. Can't say the same thing for my arms.
I counted about 15 leeches on each leg, and a whole lot had already fallen off. More were on my hands, arms, neck and head. There were so many I gave up pulling them off.
For those of us who use them normally rather than do tests for likes, Busse still works just fine.