Knuckle boom great on storm clean-up, vines, and some tangle up messes but adds a few more steps to disposal of debris. Can not see to much use in line clearing, chipper more efficient. Can't imagine company as big as Asplundh throwing that away.
Most of the trimming around here results in a few armloads of brush per tree. That's a 2 year cycle averaging 6' clearance on the primary. If a customer would request a removal, many times it was a no clean-up. That's PGE(AKA Enron) property. Scottish Power down the road cuts a big azz right of way.