I'm an ISA Arborist, I cut underneath than on top about 2-3 inches in front of bottom cut, so when the branch falls it doesn't cause any tearing of the bark ( Scaring )

Yup, that's a really good point. It's especially important with bigger branches and certain types of tree. Trees with bark like sycamore seem particularly inclined to tear if you don't do the "pre-undercut" technique. Thanks for commenting, – Angus

I have just purchased a Silky "Hayauchi" that's good for 21 feet. I think the same as you. Silky is the KING of saws.