I feel like the advantages of stereo vision may be oversold in this scenario. At the distances that sailing vessels would engage there's limited need for binocular depth cues - they really only start to come into play at the point where you would begin a boarding action
But the idea of the patches-for-night-vision is precisely to have one eye covered during the boarding, so when you enter the insides of the enemy boat that eye is ready for seeing in the dark.
I don't have binocular vision. I lived aboard a sailboat for a few years. I'm quite active with rock climbing etc and I honestly don't think I would be able to do anything better if I had binocular vision...
