12' logs are the way to go, cut 16" 18" or 24" & you come out right on. When you're in a bucket or on a rope you cut whatever length you can safely drop. Time is money & the tree's gotta come down safely & as fast as possible. Measuring takes time. Sounds like you have an excellent friendship there, I'd help him on any job you can. Cut the stuff on the sight & save his guys the time.
The day I went to work for him, I was in the back of the aforementioned dump truck with another guy, both of us doing our best to social distance (heh heh) wearing masks......And I was using my Makita and he was using a Stihl and let's just say the chips were flying like crazy. The tree guy (the boss) was bring us logs and we were bucking them up. He had banged his head on his bucket truck lift.......and wasn't in a good mood, rightfully so.......So he told the guy to just drive the wood to the dump......I actually went to the dump, recognized the maple we had cut, and filled up a truckload and drove it over to my buddy 20 miles away. At the end of the day he started counting out bills and I was like "Dude what are you doing? We're good......" and left it at that.....
For sure I keep wondering if people would specify a length of log in feet rather than 16" or 18" if they'd be more satisfied along with pleasing the tree guy in that he does not have to run his saw so much. Like amateur cutter stated, 12' or any other longer log; even a 4' will give you 3 16" logs. Perhaps this could help both parties.
When I think back to when I met him.....it totally reminds me of casablanca.....This is the beginning of a beautiful friendship.... I think it's easier for him to buck the logs because it makes dumping them a lot easier than bringing a skid steer (whether it be the dump or my house or anywhere else). At the end of the job you just want to go home...I get it and felt it that day I went to work for him. Had zero interest in splitting or even LOOKING at wood hahahaha. Never been so tired in my life.
This is what I am going to try when I have 3 oaks taken down in my yard after the new year. Can’t wait. I might be hounding you for some pointers when the time comes.