You were right to warn him. Tool injuries are very unforgiving. I'll bet he has thought about what you said and will change his way of working. I certainly hope so.
One never knows the skill level of someone. And even a skilled person occasionally slips, loses his grip or falters with damaging consequences.
As a person gets older too, the familiarity of tools may tempt one to take shortcuts. I saw this in my father as he grew older: he skipped safety precautions sometimes. He was surprised when I would warn him. But when I was a child he gave me all the warnings (more like prohibitions) so I felt justified in returning the favor. Just b/c he was 85 year old didn't mean that he would miss a finger or two any less than a child might.
One never knows the skill level of someone. And even a skilled person occasionally slips, loses his grip or falters with damaging consequences.
As a person gets older too, the familiarity of tools may tempt one to take shortcuts. I saw this in my father as he grew older: he skipped safety precautions sometimes. He was surprised when I would warn him. But when I was a child he gave me all the warnings (more like prohibitions) so I felt justified in returning the favor. Just b/c he was 85 year old didn't mean that he would miss a finger or two any less than a child might.