Was he using a double haul? Some good advice here:Q:
I've been fly-fishing for like 14 years along with a group of buddies (many of whom have been at it for much longer) and we recently asked a pro to give us some tips on improving our technique. He met us one evening in a field in Vancouver and proceeded to cast a single handed 8wt. rod loaded with a matching 8 wt. line until he literally had the entire fly line in the air. And he did so effortlessly. And by the way, it wasn't his rod... he hadn't even brought a rod with him that evening... he did that with one of my friends' rods.
What did he teach you to achieve greater distance?