You are probably right Mossy, and I like some keep track of the words
Although I did not know the English word "Breaching" - it means "breaking" in the direct translate, and of course used when things like fish break the water surface and go above so makes sense.
But ventilation is still correct IMO, as if you go over the surface, and down "perfectly" like you can do in a jump, you can actually ride on without ventilation.
So what happens is, that a part of the wing is over the surface, maybe not even over, if just the topside of the wing is on the surface, air will be sucked down and ventilation can occur, and you will drop like a rock
I dont know of poor design being able to create ventilation...
But "cavitation" yes, if a poorly designed profile at high speeds, but that is cavitation because of locally very low pressure points so the water will boil.
Got nothing to do with ventilation, which is when air from the surface is sucked down to the wing and you will lose a lot or all lift
PF