Although I can't speak to the Bristow surgery, my Bankart procedure was very successful. After already having 1 (I would say less than successful surgery) I was at the point where my shoulder would pop out when I sneezed, or any number of other minor movements. I was thinking I would be out of doing anything fun again too.
I had the work done by a sports medicine doc that had done a significant amount of work on hockey players (was a minor league's team doc) and he put it back together nice and tight. Recovery took a long time, but the shoulder feels good as new. I where a brace when I'm on the boat, but have never felt that I need one. I also have not kept up with the PT like I should, but the shoulder still feels great.
You'll be able to boat again, it will take a while to feel better, but you'll be able to get out there and enjoy things. Good luck with the cutting.