Took me 14 years to stop swinging the load before the boom was straight over it
Was setting a 6,000 lb AC unit on a roof in Tucson and the thing started drifting on me, just a slow walk to the left. The rigger on the deck said my swing was fighting my hoist and I blew him off, figured he was just nervous. Went back and looked at the video from the site camera and sure enough I was starting my swing a good two seconds before the load cleared the truck. Been running it wrong since I got my cert back in 2009. How do you all break the habit of leading the load instead of letting it come up clean?
That "slow walk to the left" is the tell every time, and good on you for actually watching the video instead of arguing with the rigger. What fixed it for me was forcing a verbal callout: boom up, load clears the truck, THEN swing. Say it out loud in the cab even if nobody hears it. Sounds dumb but your hands follow your mouth after a few weeks.
Other thing that helped was slowing my hoist down on the pick, not the swing. When the load comes up slow and clean, there's nothing to fight, so you stop wanting to lead it. The lead comes from trying to beat the load up to the roof, and that's a hurry problem, not a skill problem.
I also ran a few practice picks in the yard with a water tote where I made myself count one Mississippi after the load cleared before I touched the swing. Boring as hell but it rewires you. Fourteen years is a long groove to get out of, so expect it to feel wrong for a month before it feels right.