The only reason I've ever ran a loose chain is because I either did'nt have time to stop to tighen it at the time or was too busy to notice!
I did'nt have the experience when I cut with the "East coast loggers" as I do now, logging on my own with 2 buddies. But those guys I worked with when young could stop, break two nuts and turn the screw half turn within 10 seconds, while walking to the next tree.
I think we can agree that there's no positives that come from running a sagged chain. Unless worn tips and thrown chains are positives.
Now I can tighten my chain in about 20 seconds, while walking too, but I might trip or run into a tree
1 outta 5 times.
And all East coast lumber is'nt meek either. These west coast guys chop firs and spruce, we chop Oak and Hickory! Hardwood here boys!