I wonder if this is a risk that's under appreciated in our hobby, and oceanic watersports. If you ever go looking for various critters, on land or in the water, whether snakes, lizards, crabs, eels, whatever, it's a good idea to seek out some structure. Out in the unsheltered open is hazardous to prey, and has slim food pickings for predators. Both gravitate toward shelter.
On a North Carolina trip years ago, I see 2 big barracuda not far below the rigging under the dive boat. Just far enough to be out of the way and not worrisome, as they didn't both me, but scary just because they were so large. On the boat one way, watched a fisherman in a nearby boat reel a small one in.
I've seen some online reports where feeding was known or suspected as a factor driving attacks. I'm not automatically against feeding wildlife, I've participated in shark feeding dives (just as an observer of course), but I judge on a case-by-case basis, and I've come to think diver-fed barracuda are a risk based on reports.
Some of us got most of our pre-diving water experience on boats in freshwater, such as on fishing trips on lakes or rivers. If you wanted to splash with your feet, rinse something off, or just thrust your hand into the water to see how far under you could still see it, no problem.
If barracuda are drawn to boats, docks and piers (I've seen a small one by a pier), that might be a bad idea. Wonder how many fishermen gut/clean fish and toss scraps out of boats? And whether the barracuda learn to associate boats with food hitting the water?
Thanks for the heads up that maybe splashing that way isn't a good idea. Years ago I saw a video where a barracuda hit a yellow snapper and sliced it in half so smoothly it looked guillotined.