That sounds awful!
I may be the most prolific one handed chainsaw user both in the tree and on the ground. Does that mean I'm good? I've worked out a secret? I'm invincible? Nope... it means I've delt with the situation in front of me with a bit of thought, practiced one hand use for quite some time and am aware of the dangers and outcomes.
Every close call was my fault from bad work position and laziness.
But having found bad things happen shortly after thinking 'fu** it' & 'if I could just'
Now either of these thoughs come into my head, chain brake on, look around find the issue and mitigate the risk... move, add another rope, add a sling, use a silky, ask an opinion.... options!
One handing a saw imo is largely hype, of couse I can see the dangers.... but guess what.. most things in our line of work have associated risks! We hang from trees on 8mm prusik, chainsaw trees small enough to feed to the chipper of doom, then grind the stumps with the spinning wheel of death, all this whilst effectively deaf, and using the safety squint.
I neither encourage nor shame one handed use much the same as I don't mind if you drink a coffee whilst driving at 70 mph, both these things are calculated risks, however I will call tools down if I see something not right!
Our work is fun yes but it is not a game and the consequences can be fatal.
When battery saws are the only saws, immediate chain stop, no noise, no smell, no fear.... will one handing even be mentioned?
It isn't coincidence that stihl only sell top handles from their outlets asking for proof of tickets!
We can all guess who the majority of accidents happen too!!