How ya gonna free that boat?

during hurricanes boats go land bound and nary a scratch. a miracle.

they use helicopters in Mattapoisett to lift up boat such as this, then dump it back in the water

Never mind how to get it out. How did it get IN without shredding tree, lines, and/or the jib? Actually, I think geopelia has the right idea.

I wasn't there when the job was done, but I'd suspect it as was you outline. Sounds easiest, and surely the property owner wouldn't want his palm cut down! Either that, or aliens levitated the boat up and over ...

Remove the sail and line around the tree, pull the boat out backwards through the gap. How did they solve the problem?