Imagine a sky sphere that is basically sky and the ocean, and actual ocean mesh on the level. How can I make ocean mesh gradually blend into the sky sphere so that the scene looks seamless ? (sky sphere could be a a desert and sky, with patch of desert landscape mesh; same idea - make scene look seamless)
Does it make more sense now? Basically there is no transparency/translucency, no alpha testing, no fog of any kind. The terrain surface casts shadow / receives shadow. There is no performance loss at all (between non-blending terrain and bending terrain you see on video).