"Sin sibh fhèin, a h-uile duine!"
Translation:Well done, everybody!
OK, well, I have lived in the southeast US for years, but years ago, and never heard that expression there, nor anywhere else I've lived in the US. Interesting. I was thinking, prior to this new input from folks, that the expression probably means "that's really you!" -- one's best self. Anyway, a nice expression!