My worst moment was nearly two years ago.
I drove about 60-70 odd miles to cut up some wood at a mate's place and borrowed another mate's trailer to bring some home. He asked if I'd like to take the spare tyre. I said "No I'll be fine".
Anyway, got to the place, cracked into the 30" odd hardwood gum log with my 7900 and 32" bar. All went well until the oiler blocked up from the fine dust. Pulled the bar, cleaned the oiler, put the bar back on and run it up near the black trailer tyre to see if it was throwing oil off.
Gave my near new 7900 a rev, the bar nose lifted with the torque and stuck it straight through the sidewall of his tyre :censored:
Not only did it write his tyre off but it threw the chain, damaged a heap of drivelinks, wrecked the rubber chip deflector, and tore the crap out of the chain catcher. BUT from memory did not engage the chain brake! Also AUD$110 for a new light truck tyre for his trailer.
Other details getting a bit hazy. have tried to forget it...
The therapy lasted months.
The other problem was that when a similar thread like this popped up a while back somebody said that the funniest story they'd ever heard was about some idiot sticking their saw through a trailer tyre! Well ya prick, that was me!!!